Do You Poop Less On A Low Carb Diet

Do You Poop Less On A Low Carb Diet

A low-carb or carb-free diet can help steer you away from sugary and starchy foods like bread, pasta, and cereal. Low-carb diets are high in protein and fats and can offer an alternative to counting calories or grams. The diet isn't for everyone, however; people with medical conditions such as diabetes or high blood pressure, as well as pregnant and nursing women, should consult with their general practitioner before making significant dietary changes. Even when a lot of treats are off the table, there are still some great options for people given the go-ahead to adopt a low-carb diet.

Eggs

Eggs are an excellent low-carb food. They contain almost zero carbohydrates, but provide plenty of nutrients including vitamins A, D, E, and B, calcium, iron, phosphorus, zinc, and selenium. Egg yolks contain choline, which is essential for brain development, nerve function, muscle movement, and energy. Eggs are one of the most affordable sources of quality protein.

Fish

Seafood, including salmon, tuna, mackerel, haddock, trout, sardines, and anchovies, are free of carbohydrates. Fish is rich in fats and protein. Fatty fish, including salmon, char, mackerel, and sardines, are some of the best for your health because they contain omega-3 fatty acids that fight inflammation and lower the risk of developing conditions such as autoimmune diseases, metabolic syndrome, heart disease, Alzheimer's disease, and cancer. These nutrients are particularly vital during pregnancy; the fetal brain requires them for healthy development.

Red meat

Red meat, including beef, lamb, pork, and veal, is also carb-free, excepting organ meats like liver. Beef is full of iron and vitamin B12, which helps make DNA and keeps nerves and red blood cells healthy. Depending on the cut, meat may be more or less fatty. This makes it possible to choose your dinner options based on the ratio of fat to protein you need that day.

Poultry

Chicken, turkey, and duck are quality protein sources that contain zero carbohydrates. If you're looking for lean protein, chicken breast contains 80% protein and 20% fat. Some people on low-carb diets prefer to stick to fattier cuts such as the thigh, leg, and wing, however. Chicken provides plenty of essential vitamins and minerals and is low in cholesterol and sodium when the right portion size is properly prepared.

Cheese

Hard cheeses like Muenster, Gouda, cheddar, Colby-Jack, and Swiss are generally no more than one or two percent carbohydrate. Cheese is high in fat and a great source of protein as well. It also boasts ample quantities of vitamin B12 and calcium. Cheese comes in many flavors and textures, making it a versatile food.

Greek Yogurt

While not completely carb-free, Greek yogurt is a low-carb option, usually made up of about 12 grams per cup, and has around 40% of your recommended daily intake (RDI) of protein. It is also a great source of calcium and phosphorus. One of the most beneficial things about yogurt is its probiotic content. Probiotics are good bacteria essential to gut health. They boost immune system function, aid in nutrient absorption, and fight off bad bacteria.

Butter

Butter is approximately 80% fat and 20% water. It does not contain any carbohydrates or proteins. It is, however, a great source of vitamins A, D, and E. Butter is also rich in healthy saturated fats that raise good HDL cholesterol, but it can raise bad LDL cholesterol and as such should be consumed in moderation. The America Heart Association recommends eating only 13 grams of saturated fat every day. Butter contains many fatty acids that support brain development, as well, making it a good condiment for growing children.

Nuts and seeds

Nuts and seeds are popular low-carb diet options. These "brain foods" are an excellent source of omega-3 fatty acids and contain plenty of antioxidants for optimal brain function. Almonds are 15% carbs, 72% fats, and 13% protein; while they may not be as low-carb as walnuts, one serving has only 9 grams of carbs, about half of which is fiber. Seeds, including hemp, chia, flax, and pumpkin, are all relatively low in carbs and high in healthy fats and protein, as well. Best of all, they're an easy grab-and-go pick for snacks.

Oil

All oils are carb-free, but the healthiest are unrefined or cold-pressed, including extra-virgin olive, coconut, and avocado oils. Olive oil is loaded with antioxidants, anti-inflammatories, and anti-cancer compounds and is proven to be particularly supportive of heart health, helping fend off strokes and heart attacks.

Low-Carb vegetables

Some vegetables are high in carbs, and some are not. Low carb veggies include asparagus, mushrooms, broccoli, cauliflower, bell peppers, cucumbers, zucchini, spinach, green beans, lettuce, kale, and collard greens. Vegetables to avoid on a low-carb diet include the sweet or starchy ones such as potatoes, sweet potatoes, yams, peas, corn, parsnips, and legumes.

Avocados

Avocados are a unique fruit because instead of being high in carbs, like most of their kind, they are full of healthy fats. They have a wide and varied nutritious profile and even contain more potassium than a banana. They're an excellent source of vitamins C, E, and K, as well as B-vitamins, folate, and many essential minerals.

Low-Carb Beverages

Watch out. There are a lot of carbs hiding in sugary drinks like soda and juice. If you're on a low-carb diet, try to steer clear of beverages with added sugar. People on this diet can opt for water, coffee, tea, and sparkling water.

Do You Poop Less On A Low Carb Diet

Source: https://facty.com/food/nutrition/12-low-carb-foods-for-dieting/

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Key Functions Of Vitamin D

Key Functions Of Vitamin D

Photo Courtesy: Justin Paget/DigitalVision/Getty Images

Vitamin D is important for maintaining a healthy body, primarily because it helps you fully maximize your body's absorption and utilization of calcium, an important mineral that we all need. When paired with calcium, vitamin D helps regulate bone remodeling and growth, ensuring healthy, strong bones. Vitamin D can also help protect older adults from osteoporosis, which occurs due to excess bone loss from aging.

Furthermore, this nutrient boosts your immune system and reduces inflammation within your body, potentially warding off future medical conditions in the process. It also plays a vital role in cell growth, neuromuscular functions and protein encoding. Studies have shown that a regular, healthy vitamin D intake can also serve as an antidepressant and make people feel generally happier. But that's not all you'll want to know about vitamin D.

Vitamin D is naturally found in certain foods and now appears in many more foods that have been fortified with added nutrients. The best sources of naturally occurring vitamin D are oily fish such as salmon, tuna, cod, sardines and mackerel. Fish liver oils are another good source of vitamin D. Small amounts of the nutrient are present in beef liver, cheese, egg yolks and mushrooms.

Photo Courtesy: Alexander Spatari/Moment/Getty Images

Commonly, vitamin D-fortified foods include whole milk, orange juice, margarine and breakfast cereals. It's important to look at the label and nutrition facts to verify that vitamin D is in a particular food you're considering. Because dairy products are often fortified with vitamin D, lactose intolerant or vegan individuals should keep an eye on their diets to ensure they get enough of the vitamin.

Sun exposure is another method of naturally obtaining vitamin D, as our bodies can create their own vitamin D upon exposure to ultraviolet (UV) rays from the sun. However, it's difficult to gauge exactly how much sun exposure can generate sufficient vitamin D, as overexposure can be harmful, too. UV rays are also known to trigger free radicals, which can lead to skin cancer if left unchecked.

It's been suggested that getting approximately 15 minutes of sun exposure between 10 a.m. and 3 p.m. at least twice a week to your face, arms, legs or back will help your body synthesize enough vitamin D. It's important to note that you can't cover the exposed area of your body with sunscreen if you choose to get vitamin D naturally. The SPF blocks UV rays and can hinder your body's ability to create vitamin D. If you're in the shade or behind a window, the rays will not get through. If the climate where you live is primarily cloudy, it's important to get your recommended amount of vitamin D via other means.

Dietary supplements are also an excellent way of obtaining vitamin D. Supplements come in two forms: vitamin D3 (cholecalciferol), which is identical to the form your body makes when exposed to sunlight, and vitamin D2 (ergocalciferol), which differs slightly from D3 in its chemical side-chain structure. There's some evidence that vitamin D3 increases and maintains overall levels slightly better than vitamin D2.

Side Effects of a Vitamin D Deficiency

Vitamin D deficiency occurs when you don't adequately absorb the nutrient or when your kidneys can't convert the nutrient to its active form. This deficiency can result in medical conditions, two of which are called rickets and osteomalacia.

Photo Courtesy: RealPeopleGroup/E+/Getty Images

Rickets, a disease characterized by a failure of bone tissues to get enough minerals, can result in abnormal, soft bones and skeletal deformities. It's most common in children. Fortunately, it isn't permanent, and kids can consume as few as 1 to 3 teaspoons of cod liver oil a day to reverse the condition.

With the help of fortified foods today, rickets is almost obsolete in the United States. Osteomalacia, characterized by soft and weak bones, is usually present in adults. It's commonly treated with an intense regimen of vitamin D replacement under the care of a physician.

Vitamin D and Other Health Conditions

Vitamin D deficiency has been linked to cardiovascular disease, and people with lower levels of vitamin D appear to be at an increased risk of having a heart attack or stroke. However, the exact relationship isn't clear, and there appears to be no benefit to cardiovascular risk in taking a vitamin D supplement.

Photo Courtesy: PixelsEffect/E+/Getty Images

Research is also ongoing to find if there's a link between vitamin D and multiple sclerosis (MS). It appears that vitamin D deficiency is linked to the development of MS, and people with MS and higher levels of vitamin D appear to have reduced disease activity.

Low vitamin D has been linked to an increased risk of contracting respiratory illnesses such as influenza A. It appears that people with low vitamin D levels are at greater risk of severe novel coronavirus (COVID-19) infection. It's not clear yet if routine vitamin D supplementation would reduce this risk.

Because vitamin D is a fat-soluble substance, it can stay in your body for several days. Thus, vitamin D poisoning is possible if you supplement too much vitamin D over a period of a few months. Symptoms of vitamin D overdose include dehydration, vomiting, decreased appetite, irritability, constipation and fatigue. If left unaddressed, vitamin D poisoning can lead to anorexia, over-calcification of the bones and internal organs, kidney stones and hypertension (high blood pressure). It's important to note that vitamin D poisoning usually only occurs with excessive intake of dietary supplements. It's highly unlikely to occur as a result of normal dietary intake and sun exposure.

Daily Dosage Recommendations

The recommended dietary allowances for vitamin D vary depending on your age and other health and life circumstances, such as pregnancy. For infants under 12 months, the recommended intake is 400 international units (IU) or 10 micrograms (mcg). For individuals under 70 years old, the recommended intake is 600IU (15mcg). For individuals over 70 years old, the intake increases to 800IU (20mcg).

Photo Courtesy: katleho Seisa/E+/Getty Images

If you have a pre-existing medical condition or other medical concerns, it's best to talk to a healthcare professional about determining your recommended dietary allowance for vitamin D. This way, you can be sure the vitamin doesn't interact negatively with your condition or medication.

Resource Links:

https://medlineplus.gov/vitamind.html

https://ods.od.nih.gov/factsheets/VitaminD-Consumer/

https://www.hsph.harvard.edu/nutritionsource/vitamin-d/

https://medlineplus.gov/druginfo/meds/a620058.html

https://bestpractice.bmj.com/patient-leaflets/en-gb/pdf/3000049/Vitamin%20D%20deficiency.pdf

https://bestpractice.bmj.com/topics/en-gb/641

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/537616/SACN_Vitamin_D_and_Health_report.pdf

https://www.covid19treatmentguidelines.nih.gov/adjunctive-therapy/vitamin-d/

MORE FROM SYMPTOMFIND.COM

Key Functions Of Vitamin D

Source: https://www.symptomfind.com/health/vitamin-d-facts?utm_content=params%3Ao%3D740013%26ad%3DdirN%26qo%3DserpIndex

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Can Vitamin D Supplements Upset Your Stomach

Can Vitamin D Supplements Upset Your Stomach

Photo Courtesy: Justin Paget/DigitalVision/Getty Images

Vitamin D is important for maintaining a healthy body, primarily because it helps you fully maximize your body's absorption and utilization of calcium, an important mineral that we all need. When paired with calcium, vitamin D helps regulate bone remodeling and growth, ensuring healthy, strong bones. Vitamin D can also help protect older adults from osteoporosis, which occurs due to excess bone loss from aging.

Furthermore, this nutrient boosts your immune system and reduces inflammation within your body, potentially warding off future medical conditions in the process. It also plays a vital role in cell growth, neuromuscular functions and protein encoding. Studies have shown that a regular, healthy vitamin D intake can also serve as an antidepressant and make people feel generally happier. But that's not all you'll want to know about vitamin D.

Vitamin D is naturally found in certain foods and now appears in many more foods that have been fortified with added nutrients. The best sources of naturally occurring vitamin D are oily fish such as salmon, tuna, cod, sardines and mackerel. Fish liver oils are another good source of vitamin D. Small amounts of the nutrient are present in beef liver, cheese, egg yolks and mushrooms.

Photo Courtesy: Alexander Spatari/Moment/Getty Images

Commonly, vitamin D-fortified foods include whole milk, orange juice, margarine and breakfast cereals. It's important to look at the label and nutrition facts to verify that vitamin D is in a particular food you're considering. Because dairy products are often fortified with vitamin D, lactose intolerant or vegan individuals should keep an eye on their diets to ensure they get enough of the vitamin.

Sun exposure is another method of naturally obtaining vitamin D, as our bodies can create their own vitamin D upon exposure to ultraviolet (UV) rays from the sun. However, it's difficult to gauge exactly how much sun exposure can generate sufficient vitamin D, as overexposure can be harmful, too. UV rays are also known to trigger free radicals, which can lead to skin cancer if left unchecked.

It's been suggested that getting approximately 15 minutes of sun exposure between 10 a.m. and 3 p.m. at least twice a week to your face, arms, legs or back will help your body synthesize enough vitamin D. It's important to note that you can't cover the exposed area of your body with sunscreen if you choose to get vitamin D naturally. The SPF blocks UV rays and can hinder your body's ability to create vitamin D. If you're in the shade or behind a window, the rays will not get through. If the climate where you live is primarily cloudy, it's important to get your recommended amount of vitamin D via other means.

Dietary supplements are also an excellent way of obtaining vitamin D. Supplements come in two forms: vitamin D3 (cholecalciferol), which is identical to the form your body makes when exposed to sunlight, and vitamin D2 (ergocalciferol), which differs slightly from D3 in its chemical side-chain structure. There's some evidence that vitamin D3 increases and maintains overall levels slightly better than vitamin D2.

Side Effects of a Vitamin D Deficiency

Vitamin D deficiency occurs when you don't adequately absorb the nutrient or when your kidneys can't convert the nutrient to its active form. This deficiency can result in medical conditions, two of which are called rickets and osteomalacia.

Photo Courtesy: RealPeopleGroup/E+/Getty Images

Rickets, a disease characterized by a failure of bone tissues to get enough minerals, can result in abnormal, soft bones and skeletal deformities. It's most common in children. Fortunately, it isn't permanent, and kids can consume as few as 1 to 3 teaspoons of cod liver oil a day to reverse the condition.

With the help of fortified foods today, rickets is almost obsolete in the United States. Osteomalacia, characterized by soft and weak bones, is usually present in adults. It's commonly treated with an intense regimen of vitamin D replacement under the care of a physician.

Vitamin D and Other Health Conditions

Vitamin D deficiency has been linked to cardiovascular disease, and people with lower levels of vitamin D appear to be at an increased risk of having a heart attack or stroke. However, the exact relationship isn't clear, and there appears to be no benefit to cardiovascular risk in taking a vitamin D supplement.

Photo Courtesy: PixelsEffect/E+/Getty Images

Research is also ongoing to find if there's a link between vitamin D and multiple sclerosis (MS). It appears that vitamin D deficiency is linked to the development of MS, and people with MS and higher levels of vitamin D appear to have reduced disease activity.

Low vitamin D has been linked to an increased risk of contracting respiratory illnesses such as influenza A. It appears that people with low vitamin D levels are at greater risk of severe novel coronavirus (COVID-19) infection. It's not clear yet if routine vitamin D supplementation would reduce this risk.

Because vitamin D is a fat-soluble substance, it can stay in your body for several days. Thus, vitamin D poisoning is possible if you supplement too much vitamin D over a period of a few months. Symptoms of vitamin D overdose include dehydration, vomiting, decreased appetite, irritability, constipation and fatigue. If left unaddressed, vitamin D poisoning can lead to anorexia, over-calcification of the bones and internal organs, kidney stones and hypertension (high blood pressure). It's important to note that vitamin D poisoning usually only occurs with excessive intake of dietary supplements. It's highly unlikely to occur as a result of normal dietary intake and sun exposure.

Daily Dosage Recommendations

The recommended dietary allowances for vitamin D vary depending on your age and other health and life circumstances, such as pregnancy. For infants under 12 months, the recommended intake is 400 international units (IU) or 10 micrograms (mcg). For individuals under 70 years old, the recommended intake is 600IU (15mcg). For individuals over 70 years old, the intake increases to 800IU (20mcg).

Photo Courtesy: katleho Seisa/E+/Getty Images

If you have a pre-existing medical condition or other medical concerns, it's best to talk to a healthcare professional about determining your recommended dietary allowance for vitamin D. This way, you can be sure the vitamin doesn't interact negatively with your condition or medication.

Resource Links:

https://medlineplus.gov/vitamind.html

https://ods.od.nih.gov/factsheets/VitaminD-Consumer/

https://www.hsph.harvard.edu/nutritionsource/vitamin-d/

https://medlineplus.gov/druginfo/meds/a620058.html

https://bestpractice.bmj.com/patient-leaflets/en-gb/pdf/3000049/Vitamin%20D%20deficiency.pdf

https://bestpractice.bmj.com/topics/en-gb/641

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/537616/SACN_Vitamin_D_and_Health_report.pdf

https://www.covid19treatmentguidelines.nih.gov/adjunctive-therapy/vitamin-d/

MORE FROM SYMPTOMFIND.COM

Can Vitamin D Supplements Upset Your Stomach

Source: https://www.symptomfind.com/health/vitamin-d-facts?utm_content=params%3Ao%3D740013%26ad%3DdirN%26qo%3DserpIndex

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Vitamin D Deficiency Treatment Guidelines In India

Vitamin D Deficiency Treatment Guidelines In India

How to treat Vitamin D deficiency in sun-drenched India - guidelines

Institute of Endocrinology, Diabetes, Thyroid and Osteoporosis Disorders, Sakra World Hospitals, Varathur Hobili, Marathahalli, Bangalore, Karnataka State, India

Date of Web Publication

8-Apr-2019

Correspondence Address:
C V Harinarayan
Institute of Endocrinology, Diabetes, Thyroid and Osteoporosis Disorders, Sarka World Hospital, Bengaluru - 560 103, Karnataka
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/JCSR.JCSR_1_19

Vitamin D plays an important role in calcium and mineral metabolism. It is astonishing to find vitamin D deficiency in sun drenched country like India. This could probably due to modernisation of India-mechanization, urbanization, change in life style, dress code and revision of vitamin D adequacy range. India has the unique problem of twin nutrient deficiency- vitamin D and calcium. Low calcium in the diet coupled with vitamin D deficiency has adverse consequences in the skeletal health. Any vitamin D schedule to treat/supplement should be accompanied by adequate calcium in the diet/supplementation. There are many international guide lines for vitamin D supplementation. This review aims at highlighting the vitamin D supplementation schedule suitable in Indian context keeping in mind the cost and compliance. Studies in south India using in vitro ampoule mode with 7-dehyrocholestrol has shown adequate formation of active form of vitamin D from mid-day sun. Time of the day, latitude, and increased skin pigmentation all influence the cutaneous production of vitamin D. Exposing 12%-18% of body surface area to unprotected sunlight for 30-45 mins is equivalent to taking 600-1000 IU of vitamin D which is the dose recommended by experts for fortification of food. Vitamin D synthesized in the skin last twice as long. We as human can get Vitamin D from abundant sunshine. There are various food fortification schedules suggested. The major source of vitamin D for both children and adults is unprotected sun exposure. In the absence of sun exposure adequate amount of vitamin D from dietary sources and supplementation is a must to satisfy body's requirement. In India, adequate amount of vitamin D should be accompanied by dietary/supplemental calcium to achieve desired skeletal benefits.

Keywords: Calcium deficiency, India, Vitamin D deficiency

How to cite this article:
Harinarayan C V. How to treat Vitamin D deficiency in sun-drenched India - guidelines. J Clin Sci Res 2018;7:131-40

(See the editorial by Holick, on page 101-5, doi: 10.4103/JCSR.JCSR_3_19)

Introduction

Vitamin D is one of the oldest hormones (>500 million years). The Phytoplankton species that existed in the Sargasso Sea was found to contain a large amount of ergosterol (Vitamin D₂ precursor). Vitamin D gained essential role (to maintain a rigid skeleton in calcium poor environment) in higher terrestrial animals to cope with higher gravity.

Photobiology of Vitamin D

The 7-DHC-7-dehydrocholesterol (pro vitamin D₃-in lipid bilayer of the epidermis) is converted pre- vitamin D₃ on exposure to sunlight ultraviolet B (UV-B wavelengths 290–315 nm).^[1] This pre- vitamin D₃ undergoes conformational changes in the lipid bilayer of the skin to convert into vitamin D₃(cholecalciferol) at body temperature and is ejected from the plasma membrane into extracellular space. The liver converts vitamin D₃ into 25 hydroxy vitamin D₃(25[OH]D₃). While Vitamin D is the major storage form, 25(OH)D₃ is the major circulating form of vitamin D. 1,25 di-hydroxy vitamin D₃ is (1,25[OH]₂D₃) is synthesised by kidneys and other tissues. On excessive exposure to sunlight, pre vitamin D₃ is converted to biologically inert products (lumisterol and tachysterol). Vitamin D₂ is derived from plant sources. Most vitamin D₂ comes from yeast and mushrooms exposed to sunlight and UV radiation.

Parathyroid hormone (PTH) converts 25(OH)D₃ to 1,25(OH)₂D₃ which helps in calcium absorption from the gut. PTH is secreted when the serum calcium falls below the normal range, which resorbs the bone to maintain the serum calcium to normal (secondary hyperparathyroidism [SHPT]). PTH also increases the tubular reabsorption of calcium in the kidneys and to increase the renal production of 1,25 di-hydroxy vitamin D₃. Thus, the 'Ca-vitamin D-PTH endocrine axis' is orchestrated by Vitamin D [Figure 1].^[2]

Figure 1: Calcium-Vitamin D-parathyroid hormone endocrine axis (Copyright Permission-Nutrition Foundation of India) Click here to view

Biological Functions

1,25 dihydroxy vitamin D₃ acts through genomes (genomic actions) and chemical messengers (Rapid responses-RR) [Figure 2] genomic action take a few hours to days. The Vitamin D receptor (VDR) interacts with retinoid X receptor (RXR) to form 1,25(OH) D-RXR-VDR complex which further interacts with DNA sequences and Vitamin D-responsive elements. The RR include the opening of ion channels which occurs in few seconds to as long as 10–60 min (e.g., intestinal absorption of calcium-transcaltachia), secretion of insulin by pancreatic β-cells, the opening of voltage-gated Ca⁺⁺ and Cl⁻ channels of osteoblasts, etc.).^[3] While the non-calcaemic benefits are becoming to be understood, calcaemia benefits are well established.

Figure 2: Vitamin D actions genomes and chemical messengers (rapid responses) (Copyright Permission-Nutrition Foundation of India) Click here to view

Vitamin D and Peak Bone Mass

The peak bone mass (bone density) at the end of the growth period is attained with adequate vitamin D and calcium intake.^[4],[5],[6] An increase in dietary calcium intake during infancy, childhood and adolescence favours bone mineral accrual. To attain bone growth potential, adequate nutrition and sufficient physical activity provide the necessary mechanical impetus. Vitamin D and calcium status correlate with bone density. They have the potential to increase the peak bone mass and effectively prevent osteoporosis at late age.

Factors Affecting Vitamin D Synthesis

The ability of the skin to synthesise vitamin D is affected by: Environmental factors such as latitude, season, day and night, time of the day, the solar zenith angle (SZA), amount of cloud, ozone and aerosols, atmospheric pollution, UV index and Personal factors such as, dress code, skin pigmentation (Indians come under the skin category-type V), age (reduced ability of skin capacity with age), minimal erythemal dose (MED) and application of sun protection factor. The SZA becomes more oblique in winter and few UVB photons penetrate earth surface.^[7],[8] The SZA is also more oblique in the early morning and afternoon which is why even in India very little if any vitamin D is produced in the skin before 10 a.m. and after 3 p.m.

Normal Range of 25 Hydroxy Vitamin D (Vitamin D Status)

Serum 25-hydroxyvitamin D (25[OH]D) level is the major circulating form providing vitamin D status of an individual. Serum 25(OH)D levels (half-life 3 weeks) reflect both cutaneous synthesis and absorption from the gut. Biochemically, levels <20 ng/mL are defined as 'deficiency' and levels of 25(OH)D >30 ng/mL (to convert ng/mL to nmol/mL multiply by 2.5) are considered as 'normal'. Levels between 20 and 30 ng/mL are defined as 'insufficiency'.^[9],[10]

Magnitude of Vitamin D and Calcium Deficiency in India

Vitamin D

Vitamin D deficiency in a sun-drenched tropical country like India is surprising. About 85% of Indian population are deficient in Vitamin D. It has been shown that the 25(OH)D levels inversely correlate with latitude (r = −0.48; P < 0.0001) from the various studies in the country.^[8] The 25(OH) D levels are relatively higher in south Indian subjects (in urban and rural Andhra Pradesh ~17 ng/mL and ~19 ng/mL, respectively)^[11] compared to that of north Indians (urban northern India-children 11.8 ± 7.2 ng/mL and adolescents 13.84 ± 6.97 ng/mL).^[12] Populations studies from south India (Andhra Pradesh-latitude 13.40° N and longitude 77.2° E) have shown that agricultural labourers with their tarso (35% of body surface area) exposed for >4 h a day have vitamin D deficiency (~24 ng/mL vs. 19 ng/mL as compared to urban dwellers).^[13],[14]

Dietary calcium intake

Calcium and 1.25 dihydroxy vitamin D₃ are closely linked in their action at the cellular level. Adequate dietary calcium is necessary for bone mineral accrual. Compared to the recommended daily/dietary allowances (RDA) of the Indian Council of Medical Research (ICMR),^[15] there is a high prevalence of inadequate dietary calcium intake across rural, urban and metro population. The average (mean ± standard deviation) dietary calcium intake in India is 560 ± 310 mg/day in adults and 430 ± 180 mg/day in children.^{[11],[12],[13],[14]} The dietary calcium intake of rural, urban and metropolitan city subjects in India (mean ± standard error of mean) is 269 ± 2; 308 ± 2.3; and 526 ± 8 mg/day, respectively (P < 0.001) which is lower than ICMR recommendations^[15],[16] [Table 1]. The phytate content of the diet is high and is significantly different in the rural, urban as well as the metropolitan city groups (P < 0.0001).^{[13],[14],[16],[17]} Phytates retard/prevent the absorption of calcium from the gut.

Table 1: Daily recommended dietary allowances of calcium (mg/day) in India and USA Click here to view

Consequences of Vitamin D and Calcium Deficiency

Vitamin D deficiency affects the calcium, phosphorous and bone metabolism. With Vitamin D deficiency there is decreased efficiency of intestinal absorption of calcium and phosphorous from the diet resulting in elevated PTH levels.^{[18],[19],[20],[21]} The SHPT thus ensued, maintains the serum calcium in the normal range, mobilising the calcium from the skeleton and increasing phosphate excretion from the kidneys. The PTH-mediated osteoclastic activity weakens the bone leading to decreased bone mineral density (BMD) resulting in osteopenia and osteoporosis. The phosphaturia due to SPHT causes low normal or low-serum phosphorus levels. The result is inadequate calcium phosphorous product causing mineralisation defect.

When there is dietary calcium deficiency (high phytate diet worsens), there is SHPT with elevated 1,25(OH)₂ D₃ levels, which increase fractional absorption of calcium. When unable to meet calcium demands, there is hypocalcaemia. The lower serum phosphate cuts associated with increased levels of PTH is the cause for the mineralisation defect. This mineralisation defect is known as osteomalacia and is often undetected. This causes decrease in BMD. In children when there is little mineral in skeleton, this results in a variety of skeletal deformities known as rickets. In adults (after fusion of epiphysis), there is enough mineral in the skeleton to prevent deformities. The complaints are often aches and pains in bones and muscles.^{[22],[23],[24]} In children, they may present with difficulty in standing and walking. Elderly may have frequent falls and increasing risk of fracture.^[25],[26]

[TAG:2]Factors Responsible for High Prevalence of Vitamin D Deficiency in India^[27][/TAG:2]

Modernisation with prolonged indoor working hours, sun-shy nature of Indians, traditional clothing habits ('burqa' and 'pardah' further reduce skin exposure to sunlight in women), darker pigmentation, high atmospheric pollution, phytates in high-fibre diet, low dietary calcium intake, repeated, unplanned and unspaced pregnancies (decreased maternal stores of vitamin D) are the factors responsible.

Sources of Vitamin D and Calcium

Sources of vitamin D: Sunlight-UVB radiation, Cod liver oil, salmon fish, Mackerel, Sardines, Tuna, Egg yolk, Mushrooms (if exposed to sunlight or UV radiation).

Sources of calcium:^[15] milk and milk products (120–210 mg/100 g edible portion)– buffalo's and cow's milk– curd; about 790–1370 mg/100 g edible portion in cheese, paneer, khoa, skimmed milk; Cereals and Legumes (200–340 mg/100 g edible portion)-Ragi, whole bengal and horse gram, rajmah and soya bean; green leafy vegetables (500–800 mg/100 g edible portion)– Amaranth, cauliflower greens, curry leaves, knol-khol leaves; Nuts and oil seeds-coconut dry, almonds, hazelnuts, mustard, sunflower (130–490 mg/100 g edible portion), gingelly and cumin seeds (1080–1450 mg/100 g edible portion).

Assessment of Vitamin Status of an Individual

Serum 25OHD levels (half-life 3 weeks), is an established proxy of the vitamin D status of an individual. The concentrations of 25(OH)D in the serum reflect both absorption and cutaneous synthesis. The commercial immunoassays quantify total 25(OH)D which includes the exogenous and endogenous Vitamin D. Hence, the terminology '25(OH)D' is preferred. Unfortunately, most commercial kit assays cannot adequately measure 25-hydroxy vitamin D₂. Now that India is fortifying food with vitamin D₂ this will be a major issue in the assessment of Vitamin D status of an individual. Assessment of active form 1,25(OH)₂D₃(half-life 4–6 h) is not used to estimate the vitamin D status of an individual except in conditions such as acquired and inherited disorders of vitamin D and phosphate metabolism.

Candidates for Screening

Metabolic bone diseases– Rickets, osteomalacia, osteoporosis, older adults with history of falls/or non-traumatic fractures; pregnant and lactating women; Chronic hepatic and renal failure; Pancreatic diseases– cystic fibrosis, calcific pancreatitis; post-whipple procedure; Disorders of gut– Inflammatory bowel diseases, Crohn's disease, malabsorption syndromes, radiation enteritis; post-bariatric surgery; hyperparathyroidism; granulomatous disorders– tuberculosis; sarcoid; fungal diseases– histoplasmosis, coccidiomycosis, some lymphomas and those on medications– anti-seizure medications; glucocorticoids; antifungals and cholestyramine.

Recommended Dietary Allowances of Calcium and Vitamin D for Indians

The RDA of calcium (mg/day) (both genders) for Infants 0–1 year 500, children 1–9 years 600; for children 10–18 years 800; for adults is 600; and for pregnant and lactating women 1200 as per the revised guidelines of ICMR [Table 1].^[15] The committee was of the view that Vitamin D fortification and supplementation pertain to the population in developed countries where there is limited sunlight exposure. The committee felt that outdoor physical activity was not only a means of achieving adequate synthesis of Vitamin D but also helps in controlling overweight and obesity. The previous recommendation of 400 IU/day for adults was retained.

The RDA of calcium (mg/day) of USA^[17] is-Infants 0–1 year 500, children 1–9 years 800; 10–18 years 1200–1300; adults (both genders) 800–1000; pregnant and lactating mothers 1200–1300 [Table 1]. The Vitamin D recommendation for the general population, of various societies are given in [Table 2].^{[17],[27],[28],[29],[30],[31]}

Table 2: Daily recommended dietary allowances of vitamin D-of various societies and proposed guidelines Click here to view

Concept and Basis of Vitamin D Supplementation

SPHT occurs when the 25(OH)D levels are <20 ng/dl. SPHT leashes the bone, conserves calcium from the kidneys and converts 25(OH)D to 1,25(OH)₂D and helps in calcium absorption from gut to maintain serum calcium level to normal. Hence, vitamin D and calcium supplementation therapy are to suppress SPHT and help in bone accretion. When the vitamin D status is low only 10%–15% of dietary calcium and 60% of phosphorous is absorbed. Vitamin D sufficiency enhances the calcium absorption by 30%–40% and phosphorous absorption by 80%.

Pharmacological Preparations of Vitamin D and Calcium

Cholecalciferol is the drug recommended for the general population, the population at risk and treatment of vitamin D deficiency. Vitamin D₂ should also be included for pharmacological preparations since vegetarians will not take vitamin D₃. The blood level increase in 25-hydroxy vitamin D depends on the baseline blood level in response to Vitamin D. There is a robust increase in 25-hydroxy vitamin D levels with small amounts of Vitamin D when blood levels of 25-hydroxy vitamin D are <20 ng/mL. Thereafter for every 100 IUs suggested the blood levels of 25-hydroxy vitamin D increase by 0.6–1 ng/mL.^[28]

Analogues such as 1α-(OH)D₃, 1α-(OH)D₂, 1,25(OH)₂D₃, 19-nor-1α,25(OH)₂D₂, 22-oxa-1α, 25(OH)₂D₃, 25(OH)₂D₃, should not be used to manage Vitamin D deficiency. They are used in the chronic renal disease when associated with disorders of Vitamin D hydroxylation.

Calcium carbonate and citrate are the most common forms of calcium preparation. Calcium carbonate is given immediately after a meal to ensure optimal absorption (1250 mg of calcium carbonate gives 500 mg of elemental calcium, which is the maximal dose of calcium given at a time). Calcium citrate can be taken without meals and is the supplement of choice in a patient with achlorhydria and those taking proton pump blockers and histamine-2 blockers. Calcium from calcium citrate is slightly better absorbed than calcium from calcium carbonate. Calcium carbonate is the least expensive and is what often is recommended. It should be taken with a meal if at all possible. Studies by Recker have shown that calcium carbonate is perfectly absorbed in achlorhydric patients as long as it is taken with a meal.^[32] It is not absorbed on an empty stomach if the calcium carbonate is in some type of pill form.^[32] Calcium gluconate and lactate are less concentrated form of calcium and are not practical for supplementation in oral form. The upper tolerable (UL) limit for calcium is 2500 mg/day.

Absorption of Vitamin D and Calcium

Vitamin D is absorbed into the lymphatic system through chylomicrons. Vitamin D metabolite 1,25(OH)₂D₃ uses VDR to regulate intestinal calcium absorption. Four models of vitamin-D-regulated intestinal calcium absorption are proposed, namely, facilitated diffusion, vesicular trafficking, transcaltachia and regulated paracellular transport.

[TAG:2]Recommended Dietary Intake of Vitamin D for Patients at Risk [Table 2]^{[17],[28],[29],[30],[31],[32]}[/TAG:2]

The candidate at risk for vitamin D deficiency is those mentioned under the section-screening. In these individuals' supplementation is to be implemented to maintain the serum 25(OH)D concentration >30 ng/mL. For both genders, the daily vitamin D requirements (IU/day) for infants and children 0–1 year require 400 IU; 1–18 years 600 IU. To raise the serum 25(OH)D concentrations consistently >30 ng/ml may require 1000 IU/day. For age 19–70 years require 600 IU/day. To maintain serum concentrations consistently >30 ng/ml may require 1500–2000 IU/day. Adults 70 years and above require 600–800 IU/day and at least 1500–2000 IU/day to raise the 25(OH) D levels >30 ng/ml consistently. In pregnancy and lactation at least 600 IU/day of vitamin D is required. 1500–2000 IU/day may be required to maintain blood levels of 25(OH)D above consistently 30 ng/mL. Night workers and dark-skinned adults require 1000–2000 IU/day throughout the whole year. Obese individuals require 2–3 times the dose required for age-matched peers with normal body weight.^[33] The tolerable upper intake level (both genders) for infants 0–12 months is 2000 IU; children 1–18 years 4000 IU; adults 19–70 years 10,000 IU; and pregnancy and lactation 10,000 IU.

Vitamin D Supplementation Based on 25(Oh)d Concentrations

25(OH)D levels 0–20 ng/mL

The therapeutic dose of vitamin D should be supplemented and treatment carried out until the 25(OH)D concentrations of >30 ng/mL is reached. The dose 0–1 year of age is 2000 IU/day; 1–18 years 4000 IU/day; adults (19–70 years) and elderly (>70 years) 10,000 IU/day. Alternatively, adults and elderly can be given 60,000 IU/weekly for 8 weeks to achieve 25(OH)D concentrations of >30 ng/mL and followed by maintenance dose for their respective age. In patients with skeletal symptoms, it is necessary to assess and monitor a parameter of calcium and phosphate metabolism (serum calcium, phosphorous, alkaline phosphatase, PTH and calcium/creatinine ratio).

25(OH)D levels 20–30 ng/mL

Verify if the patient was already on appropriate vitamin D supplementation schedule the regularity of dose, intake, type of preparation and way of supply. If appropriate, increase the dose by 50% and reassess after 6 months. If vitamin D was not supplemented previously, consider starting vitamin D intake as recommended for the general population.

25 OH levels >30 ng/mL

When the patient is on optimal vitamin D levels and on supplementation, it is advisable to continue the previous management. In those not on supplementation to consider starting Vitamin D intake as recommended for the general population.

Stoss Therapy

"Stossen" (German) means to push. Stoss therapy involves pushing large doses of cholecalciferol to treat nutritional rickets.^[34] The basis of this therapeutic approach is that adipose tissue and muscles efficiently store cholecalciferol after a single large dose. There is continued conversion into active metabolite 1,25(OH)₂D₃ to heal rickets. In a country like India, with limited resources, compliance and cost are the major advantages of single-dose intramuscular stoss therapy over daily, weekly regimes or oral stoss therapy. Cholecalciferol 600,000 IU deep intramuscular (for >18 years age) would maintain serum levels adequately and supress PTH. The second dose should not be repeated until the next 8 weeks. Stoss therapy should be followed by maintenance dose of vitamin D and adequate dietary calcium intake.^[35] Calcitriol is not used for stoss therapy.

Indian Experience

In India, most supplementation schedules in adults for correcting vitamin D deficiency have shown that with a dosage of cholecalciferol 60,000 IU/weekly for 8 weeks (with or without calcium supplementation) have achieved normal serum levels of 25(OH)D at the end 2 months.^{[36],[37],[38]} When the supplementation is not followed by maintenance schedule the serum 25(OH)D levels drift back. Hence, they need to be followed up with cholecalciferol 60,000 IU/once a month.

In a study conducted in India,^[38],[39] vitamin D supplementation (based on the Endocrine Society Clinical Practice Guidelines), even up to UL intake levels along with elemental calcium of 1 g/day is safe and does not lead to hypercalcaemia. In another study conducted in India, parental dose of 600,000 IU of cholecalciferol/deep IM stat followed by maintenance cholecalciferol therapy was compared with cholecalciferol 60,000 IU/weekly for 8 weeks followed by maintenance cholecalciferol therapy.^[39] Both groups received elemental calcium throughout. Both groups achieved similar serum calcium, 25 OH D levels and suppression of PTH.^[39] Parenteral dose of 600,000 IU of cholecalciferol/deep IM stat SHOULD NOT be repeated until the 8^th week. After 8 weeks, oral cholecalciferol 60,000 IU/once a month can be given.^[39] Loading doses of cholecalciferol (oral or parenteral) are not reccomended in pregnant women unless the patient has symptomatic vitamin D deficiency (tetany or symptomatic hypocalcaemia). Daily requirement of cholecalciferol in pregnancy is 2000 IU/day. The UL limit of cholecalciferol supplementation is 10,000 IU/day.

Thus, a simple supplemental dose without adequate loading doses may not be sufficient to achieve therapeutic levels. Similarly, after a loading dose, if not sustained in the long term with supplemental dose may not give desired benefits. In the Indian context, Vitamin D supplementation if not accompanied by adequate calcium supplementation may not achieve desired skeletal benefits. Iron is not combined with calcium.

Monitoring of Vitamin D Treatment

Because of the cost of 25(OH)D estimation repeated estimation of 25(OH)D is not advised. However, repeat estimations of 25(OH)D is undertaken in at-risk patients when there is no desired response in patients treated with metabolic bone diseases.^[28] A serum calcium level of 10.5–11 mg/dL and above point to vitamin D toxicity. A baseline serum calcium helps in follow-up. Fasting urine calcium-to-creatinine ratio (calcium and creatinine measured as milligrams/dL in random urine specimens) of 0.25 and above is an indirect indicator of vitamin D excess.

Duration of Therapy

Once 25(OH)D concentrations of >30 ng/mL is reached, maintaining the serum levels along with adequate calcium supplementation is important. Adequate 25(OH)D levels will suppress SHPT. To calcify the osteoid formed due to vitamin D deficiency adequate calcium is important. It has been shown from bone histomorphometric studies that subjects with 25(OH)D levels <20 ng/dL have wide osteoid seams and may take anywhere from 10 to 15 years to mineralize (mineralization lag time) their bones.^[40] Hence, maintaining adequate 25(OH)D levels >30 ng/mL with adequate dietary calcium is imperative for skeletal health.

Vitamin D Toxicity

Serum concentrations of 25(OH) D >150 ng/mL (375 nml/L) is considered as toxicity and levels up to 100 ng/ml (250 nmol/L) are cited as safe for both children and adults.^[41] Serum 25(OH)D concentrations are elevated associated with hypercalcaemia or hypercalciuria and suppressed PTH. Patients present with clinical features of lethargy, vomiting, polyuria, polydipsia, altered sensorium, weight loss, nausea, constipation, renal dysfunction, renal calculi, muscle weakness, hypertension, neuropsychiatric disturbances, cardiac arrhythmias and ultimately death. It is commonly due to overdosing by prescriptions or intake by patient with high doses of vitamin D doses that exceed suggested recommendations.

Vitamin D Hypersensitivity

The UL value is the highest value of vitamin D oral intake which is unlikely to produce risk of adverse effects during growth and maturation, adulthood and ageing. Two conditions to the exception of the rule are-granulomatous diseases and genetic defect or absence of 24-hydroxylase (CYP24A1).^[42] In granulomatous diseases like sarcoid, there is excess extrarenal 1-alpha-hydroxylase. This leads to excessive and uncontrolled production of calcitriol (1,25[OH]₂D₃) resulting in low 25(OH)D levels. In these conditions, the recommended target for serum 25(OH)D is 25 ng/mL.

The active form of Vitamin D 1,25(OH)₂D₃ is formed by 1-alpha-hydroxylase (CYP27B1). The levels of 25(OH)D and 1,25(OH)₂D₃ is regulated by cleavage reaction of 24-hydroxylase (CYP27A1). This enzyme catalyses 25(OH) D and 1,25(OH)₂D₃ to inert metabolites. Mutations of CYP27A1 gene coding 24-hydroxylase^[43] or excessive synthesis 1,25(OH)₂D₃ of resulting from the mutation of SLC34A1 gene coding sodium-phosphate co-transporter (NaPi-IIA) in the kidney^[44] can result in a risk of hypervitaminosis D even in prophylactive doses of Vitamin D.

Sunlight and Vitamin D

The most physiological relevant and efficient way of acquiring vitamin D, in locations around the equator (between latitudes 42° N and 42° S) is endogenous synthesis from the skin. A minimum of 30 min skin exposure (without sunscreen) of the arms and face to mid-day sun will be sufficient for the day requirement. Vitamin D synthesised in the skin lasts twice as longer in the body compared to ingested/supplemented dose. Exposure of body in bathing suit (almost 100% of body surface area) to sunlight causes slight pinkness (1 MED) is equivalent to ingesting approximately 20,000 IU of vitamin D orally.^[45] Applying the rule of nines Burns chart, exposure of both forearms and face is equivalent to exposing 12% of body surface area. Exposure of 1 MED two to three times a week can meet the body's requirement of Vitamin D (Holick's Rule). '1 Standard vitamin D Dose' (SDD) is the time required to obtain recommended UV dose for adequate vitamin D synthesis.^[46] For Asians with skin type V, 1 SDD at 11.5° N is 10–15 min, and at 29° N is 10–45 min at solar noon, with longer durations in winter. Vitamin D synthesis can be reduced and force 'Vitamin D winter' when there are clouds, aerosols and dense ozone.^[47] India is located at between 8.4° and 37.6°N.

A study conducted from Tirupati (latitude 13.4° N and longitude 77.2° E, south India) using 'in vitro' ampoule model with precursors of vitamin D (7-dehydrocholesterol), when exposed to sunlight, converted to active Vitamin D best in mid-day sun (between 11 a.m. to 2 p.m).^[8] From the various Indian studies in the literature, there is a strong inverse correlation between the 25(OH)D levels and latitude (r = −0.48; P < 0.0001). The 25(OH)D levels in South Indian subjects are relatively higher than in subjects in North India clearly establishing the relationship between closeness to the equator (smaller zenith angle) and natural Vitamin D synthesis.^[8]

In another study,^[48] authors assessed serum 25(OH)D and bioavailable 25(OH)D in males with varying durations of sun-exposure between indoor and outdoor environments in Delhi (latitude 28.38° N and longitude 77.12° E) during August–September. They demonstrated that outdoor workers with prolonged sun-exposure were vitamin D-sufficient, with higher serum bioavailable 25(OH)D than the indoor workers during summer. Studies from Pune (latitude 18.31° N and longitude 73.55° E) have shown that toddlers exposed to sunlight (playing outside) for more than 30 min-a-day exposing more than 40% of their body surface area have a normal Vitamin D status which was three times more compared with the toddlers who were indoors for most part of the day.^[49] Hence, the association between Sunlight exposure and vitamin D synthesis is well established in South Asians. We as human can get vitamin D from abundant sunshine. The position statement for vitamin D and health in adults in Australia and New Zealand recommends a walk for 6-7 mins mid-morning or mid afternoon in summer and as much bare skin exposed as feasible for 7-40 mins at noon in winter, for fair-skinned people on most days to maintain adequate vitamin D levels in the body.^[50]

Fortification of Foods

India has the unique burden of 'twin nutrient deficiency'– vitamin D and calcium. Any public health measures which address the problem in isolation may not have the desired skeletal benefits in the long term. Recently, in India, milk and cooking oil is being fortified with vitamin D. There are many reports^{[51],[52],[53],[54],[55],[56]} and proposal for fortification process.

India has 1.33 billion population with a rural-urban distribution: 68.84% and 31.16%. There has been a spurt in growth of population in Urban areas in the country, which could be due to: migration, natural increase and inclusion of new areas under 'urban' in the census. Majority of rural population sell their produce (milk, vegetables, grains, etc.,) to the urban for their lively hood.^[13],[14] Only 35% of the Indian populations have access to regulated milk supply. India ranks 97 among the 118 developed countries in Global Hunger Index.

Any fortification measure should reach the population as a whole. Majority of the population in rural areas do not have accesses to organised food supply chain (dairy and nondairy products) in India, especially the rural and semi-urban areas. However, they do have a better opportunity to sun exposure. In a study form Delhi slums,^[57] it was shown that toddlers who were exposed to sunlight had better vitamin D status (~100 nmol/L) than those who were not (~20 nmol/L). The families whose toddlers were exposed to the sun were given educational material by local healthcare workers explaining the benefits of sunshine.

Food fortification process needs to be initiated with an aim to improve distribution through organised sector with good surveillance. Increasing efforts to mobilise available resources that would improve knowledge and education about the benefits of sun exposure for 30 min, by exposing 12%–18% of body area for 30–45 min a day without sunscreen along with enhancing the dietary calcium intake would go a long way much before the food fortification program become a reality. Pragmatically, in those areas with abundant sunshine, school teachers should educate their students to expose them to sunlight during lunch hour (sunshine hour). Toddler, children, elderly adults should be encouraged to expose to mid say sun. Working classes can be encouraged to take a walk in the sun post-lunch. Such an approach with equal emphasis on knowledge on dietary calcium and importance of sunlight exposure will go a long way in improving the current status.^[58] While the majority of the urban resident who have limited to sun exposure must supplement with vitamin D and calcium and should have food fortified in vitamin D and calcium to meet their daily requirements.

The major source of vitamin D for both children and adults is unprotected sun exposure. In the absence of sun exposure, adequate amount of Vitamin D from dietary sources and supplementation is a must to satisfy body's requirement. In India, an adequate amount of Vitamin D should be accompanied by dietary/supplemental calcium to achieve desired skeletal benefits.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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58.	Harinarayan C V. Vitamin D Deficiency in Sun Drenched India – Can D-lightful Sunlight Be a Respite? – Sunlight D lemma. Proc Indian Natn Sci Acad 2018;84;923-35.

  [Figure 1], [Figure 2]
  [Table 1], [Table 2]

Vitamin D Deficiency Treatment Guidelines In India

Source: https://www.jcsr.co.in/article.asp?issn=2277-5706;year=2018;volume=7;issue=3;spage=131;epage=140;aulast=Harinarayan#:~:text=In%20India%2C%20most%20supplementation%20schedules,at%20the%20end%202%20months.

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