Here Comes The Sun(shine): All You Need To Know About Vitamin D

A 33-year-old friend has a vitamin D deficiency, as do my 82-year-old grandma and a colleague’s father. If it’s not evident from the frequency in my small social sphere, many studies have shown that vitamin D deficiency is rampant in India. While the causes of vitamin D deficiency are plenty — pollution, low intake of vitamin D-rich foods, our inherent increased skin pigmentation, and even cultural norms — it’s possible to increase levels naturally. 

Vitamin D deficiency prevails in epidemic proportions all over the Indian subcontinent, with a prevalence of 70–100% in the general population.

Dr Divya Gopal, Consultant, Internal Medicine, Sir HN Reliance Foundation Hospital, Mumbai, shines a light on the sunshine vitamin’s superpowers, why deficiencies are rampant, and how to bring levels up at home.

Dr Divya explains that vitamin D is a fat-soluble vitamin (which dissolves in fats and oils and can be stored in your body over time) essential for human health. The "sunshine vitamin" moniker comes from the fact that the body can produce it naturally when exposed to sunlight — ultraviolet B (UVB) rays from the sun trigger the body to synthesise vitamin D under the skin.

The Sunshine Vitamin comes from two primary sources:

1. Dietary vitamin D: Foods like fatty fish (salmon, tuna, mackerel), fortified dairy products (milk, yoghurt), and egg yolk are rich in vitamin D, which is absorbed through the small intestine.
2. Sunlight-induced vitamin D: The skin synthesises vitamin D from cholesterol when exposed to UVB rays — synthesised vitamin D is then routed to the liver and kidneys for activation.

Vitamin D plays a crucial role in:

• Bone Health: It helps regulate calcium and phosphorus absorption, which is essential for strong bones and teeth. Vitamin D, the happy helper, aids the body to absorb calcium from the intestines. Without enough vitamin D, calcium absorption is hampered, and you have weak and fragile bones.
• Immunity: Vitamin D has been shown to support the immune system, and helps battle various infections.
• Mood stabilisation: Low levels have been linked to mood disorders like depression and anxiety, in a few studies.
• Heart health: Adequate levels can help reduce the risk of heart disease by regulating blood pressure and cholesterol levels.
• Muscle function: Vitamin D is involved in muscle strength, stamina and function.

Menstrual health: Vitamin D affects oestrogen and progesterone levels, influencing irregularities, menopause, fertility, and pregnancy.

Optimal vitamin D levels vary depending on age, health, diet, and geography, so a doctor can verify if your levels are on point. But if you’re feeling constant fatigue, bone pain, frequent muscle weakness, or mood changes — skip the search engine wormhole, consult a doctor, and use blood tests to assess your levels, as these can be stealthy and subtle symptoms of a vitamin D deficiency. 

Exclusively breastfed infants, older adults, overweight people, and those with darker skin and health conditions like kidney and celiac disease are more prone to deficiencies. Deficiencies occur when food intake is lower, sunlight exposure is limited, or kidneys can’t convert it to its active form.

Prolonged vitamin D deficiency can lead to more serious health issues, such as osteoporosis, rickets, elevated possibility of autoimmune diseases, and increased risk of infections. 

While there’s no “quick fix” to increasing levels, Dr Divya Gopal’s three-fold plan includes:

1. Going outdoors during peak sunlight hours, at least 5 days for between 5-30 minutes — a walk will give you exercise and Vitamin D (two birds, one stone)
2. Incorporating fatty fish, salmon, tuna, mackerel, sardines, and fortified dairy products like milk and yoghurt, cheese, egg yolks, and fortified cereals into your diet.
3. Checking vitamin D levels annually and consulting with healthcare professionals who may suggest Vitamin D supplements.

According to Dr Divya Gopal, vitamin D-rich foods include fatty fish like salmon, tuna, mackerel, and sardines, fortified dairy products like milk, yoghurt, cheese, egg yolks, and fortified cereals.

Dr Divya clarifies that there are no quick fixes to raising vitamin D levels, but spending time in the sun and consuming vitamin D-rich foods can help boost levels over time. Consult a healthcare provider for guidance if you're concerned about your vitamin D status.

If you want to increase your vitamin D levels naturally, opt for a two-fold plan. Increase your sunlight exposure during peak sunlight hours, but as Baz Luhrmann said, remember to wear sunscreen. You can also increase your intake of vitamin D-rich foods, as listed above. 

It may not be instant, but over time, you may see an increase in your vitamin D levels — assuming you don’t suffer from any conditions like kidney disease, malabsorption disorders, and celiac disease that impair vitamin D absorption. Certain groups, like older adults, overweight people, breastfeeding mothers, and people with darker skin, tend to be prone to lower vitamin D levels, so they might have to seek professional advice to increase their levels.

Dr Divya says, “While dry fruits generally don't contain significant amounts of vitamin D, some fortified options may be available. Check the labels for vitamin D content.”