• When UVB rays come in contact with our skin, vitamin D formation is started.
• Our skin has a natural substance, 7-dehydrocholesterol.
• When UVB rays come in contact with 7-dehydrocholesterol, it converts into Vitamin D3 (cholecalciferol).
• This Vitamin D3 (cholecalciferol) converts into active vitamin D (calcitriol) in the liver and kidneys.
• This active form helps in calcium absorption, bone strengthening, immunity, etc.

Best time and duration for exposure 

• 15 to 30 minutes (face, arm, hand)
• 8 am to 11 am in India

    2. Fortified Milk & Dairy Products

      What are Fortified foods?

• Fortified food is that which has added minerals or vitamins to increase its nutritional value.
• There are many brands in India easily available with a label of fortified vitamin D or calcium.

      What to check while buying fortified products

• Check the label, it should be fortified with vitamin D.
• Check the exact amount of vitamin D per serving in the nutritional panel.

      Which type of vitamin D

• D2 (ergocalciferol) — plant-based
• D3 (cholecalciferol) — more effective, usually animal-based (but now vegetarian D3 is also available ).

• Check for added sugar for enhancing taste, and avoid it.

Last check Expiry date/Food safety certificate, and choose trusted brands.

 3. Fortified Plant-based Milks (Soy, Almond, Oat)

💡Benefits of fortified plant-based milk

• ✅ Lactose-free (no issues for lactose intolerance)
  ✅ Vegan-friendly (completely plant-based)
  ✅ Extra vitamin D, calcium & vitamin B12 
  ✅ Cholesterol-free & generally low fat

4. Fortified Cereals & Oats

• Easy breakfast option

• Indian available brands

• It can be combined with milk to increase nutrition.

 5. Mushrooms Exposed to Sunlight

• Normal mushrooms (no sunlight): almost zero vitamin D.
• Sun-exposed mushrooms: 400–500 IU vitamin D per 100 g (depends on exposure time).
• Button mushrooms (most common)
• Mushrooms contain one compound, ergosterol, after exposure to sunlight, converts into vitamin D.
• In daily cooking, one can enhance vitamin D concentration in mushrooms by keeping them in direct sunlight (clean space) for 30 minutes.

 6. Fortified Orange Juice

• It is easily available in India

• Points should be considered before consuming

1. It can be high in sugar.
2. Overconsumption can add extra calories.
3. Not a complete substitute for whole fruit(lacks fiber).

 7. Sprouted & Fortified Tofu

• Sprouted tofu is made from sprouted soybeans(the beans are allowed to germinate before making tofu)
• These are easy to digest and rich in nutrients.
• Fortified tofu is usually fortified with calcium, vitamin B12, and vitamin D.

8. Supplements (Doctor-Recommended)

When supplements are necessary

• Certain medical conditions: 1)malabsorption disorders, eg, Crohn’s disease, Ulcerative colitis. 2) liver or kidney disease.

• Pregnancy & breastfeeding.
• Older adults
• Osteoporosis
• Rickets in children

 Dosage of vitamin D supplements

• Dosage depends on the deficiency, whether it is mild or severe.

Daily requirement of vitamin D

• Group	Recommended Daily Vitamin D Requirement
  Adult male	600–800 IU (15–20 mcg)
  Adult female	600–800 IU (15–20 mcg)
  Children (1–18 years)	600 IU (15 mcg)
  Infants (0–12 months)	400 IU (10 mcg)
  Pregnant women	600–800 IU (15–20 mcg)
  Lactating mothers	600–800 IU (15–20 mcg)

  Notes:

  ✅ IU = International Units; 1 mcg vitamin D = 40 IU.
  
  ✅ Sunlight exposure also plays an important role, but dietary/supplemental intake is still necessary in most cases.

  How much Vitamin D do we get from Fortified food?

If one day plan is like given below:

• 1 glass fortified milk (100 IU)
• 1 bowl fortified cereal (80 IU)
• 1 cup fortified yogurt (80 IU
• Then it will be approx 260 IU, and the remaining we get from sunlight exposure.
• Please check the amount of vitamin D/serving in your case.