Published on Mar 20, 2025 7 min read

How to Get Enough Vitamin D: Sunlight or Supplements?

Vitamin D is vital for bone health, immune function, and overall well-being. It helps the body absorb calcium and phosphorus, essential for strong bones and teeth. A deficiency can lead to fatigue, muscle weakness, and a higher risk of fractures. This article explores how to maintain healthy vitamin D levels through sunlight, diet, and supplements.

Why Do You Need Vitamin D?

Your body requires vitamin D as an essential dietary substance. The main function of Vitamin D precisely supports your body's calcium absorption process to strengthen your bones and teeth. The absence of vitamin D in your body leads to weak bones that increase the risk of developing the bone condition osteoporosis. Besides its bone-strengthening benefits vitamin D provides additional health benefits which include:

• Your immune system receives power from Vitamin D as it protects your body from diseases by combating infections and reducing both inflammation and colds.
• The strength of your muscles and your ability to maintain balance depend on vitamin D which decreases the risk of accidents for senior citizens.
• The deficiency of vitamin D causes depression together with seasonal affective disorder (SAD) and tiredness. Serotonin hormone levels increase because of vitamin D intake thus enhancing mental health.
• Research indicates vitamin D supplementation may decrease risks for heart disease along with type 2 diabetes and breast or colorectal cancer as well as heart diseases. The research continues while preliminary findings suggest positive outcomes.

How Much Vitamin D Do You Need Daily?

The amount of vitamin D you need depends on age, lifestyle, and health conditions. The recommended daily intake (RDI) is:

• Infants (0-12 months): 400 IU (10 mcg)
• Children (1-18 years): 600 IU (15 mcg)
• Adults (19-70 years): 600 IU (15 mcg)
• Adults over 70 years: 800 IU (20 mcg)

Some people may need more vitamin D due to health conditions or limited sun exposure. A doctor can check vitamin D levels through a blood test and recommend the right dosage if needed.

Sunlight: The Best Natural Source of Vitamin D

Sunlight helps your body make vitamin D, which is important for your health. Vitamin D makes your bones strong by helping absorb calcium. It also boosts your immune system and can improve your mood. When the sun touches your skin, your body makes vitamin D naturally. Spending time in the sun is an easy way to get it, but don’t stay out too long. Too much sun can harm your skin and raise the chance of skin cancer.

How Does Sunlight Help Produce Vitamin D?

Your body makes vitamin D naturally when your skin is exposed to sunlight. Specifically, UVB rays from the sun help your skin turn cholesterol into a type of vitamin D. This vitamin is later processed by your liver and kidneys into a form your body can use.

While sunlight is key for vitamin D, several factors can affect how much your body makes:

What Affects Vitamin D from Sunlight?

• Time of Day: The best time for vitamin D is 10 a.m. to 3 p.m., when UVB rays are strongest. Early morning or late afternoon sunlight is less effective because UVB is weaker then.
• Skin Type: Lighter skin makes vitamin D faster because there's less melanin (a pigment that blocks UVB). Darker skin, with more melanin, needs more sun exposure to make the same amount of vitamin D.
• Where You Live: People closer to the equator get stronger sunlight year-round, making it easier to produce vitamin D. Those farther north may struggle, especially in winter when UVB rays are weaker.
• Season: Vitamin D production peaks in summer due to longer, sunnier days. In winter, shorter days and weaker sunlight often mean little to no vitamin D production in some areas.
• Sunscreen: Sunscreen protects your skin from harmful UV rays but also blocks UVB, which can limit vitamin D production. Experts suggest short, unprotected sun exposure (10-15 minutes) before applying sunscreen.
• Clothing: Covering your skin with clothing or hats reduces UVB absorption, which lowers vitamin D production. The more skin you expose, the more vitamin D your body can make.

Knowing these factors can help you better manage your vitamin D levels naturally.

How Much Sunlight Do You Need?

Experts recommend getting 10 to 30 minutes of direct sunlight on bare skin (like your arms, legs, or face) a few times a week. The exact time depends on your skin type and where you live. People with lighter skin may need less time, while those with darker skin might need more to produce enough vitamin D.

But remember, too much sun can harm your skin. The goal is to get just enough sunlight for vitamin D without risking sunburn or long-term damage.

What If You Don’t Get Enough Sunlight?

If you’re indoors a lot, live in a low-sunlight area, or use sunscreen often, you might not get enough vitamin D from the sun. Instead, try:

• Fortified foods (milk, cereal, orange juice)
• Fatty fish (salmon, mackerel)
• Egg yolks
• Vitamin D supplements

If you have specific health or diet needs, talk to a doctor about whether supplements are right for you.

Finding the Right Balance

Sunlight is a great way to boost vitamin D, but it’s important to balance it with other sources. Manage your sun exposure and add foods or supplements as needed to maintain healthy levels. This supports strong bones, your immune system, and overall health.

Best Food Sources of Vitamin D

Sunlight is the best way to get vitamin D, but you can also get it from food.

Foods with Vitamin D:

• Fatty fish: Salmon, mackerel, sardines, and tuna have lots of vitamin D.
• Egg yolks: The yolk in eggs has a little vitamin D.
• Fortified foods: Some milk, cereal, and orange juice have added vitamin D.
• Cheese: Cheddar and other cheeses have small amounts of vitamin D.
• Mushrooms: Certain mushrooms make vitamin D when they get sunlight.

Eating these foods can help increase your vitamin D, but sometimes food isn’t enough for everyone.

Do You Need Vitamin D Supplements?

Vitamin D supplements are helpful for people who:

• Don’t get much sunlight or stay indoors a lot.
• Have darker skin, as they make less vitamin D from the sun.
• Are older, since aging makes it harder to produce vitamin D.
• Follow a vegan or vegetarian diet without natural vitamin D sources.
• Have health issues like celiac or Crohn’s disease that make it hard to absorb vitamin D.

Choosing the Right Vitamin D Supplement

There are two main types of vitamin D supplements:

• Vitamin D2 (Ergocalciferol): Found in plant-based sources and less effective in raising blood vitamin D levels.
• Vitamin D3 (Cholecalciferol): Found in animal-based sources and more effective in maintaining vitamin D levels.

When choosing a supplement, consider:

• Dosage: Stick to the recommended daily intake unless advised otherwise by a healthcare provider.
• Form: Vitamin D3 is the preferred form as it is better absorbed by the body.
• Quality: Look for third-party tested supplements to ensure purity and safety.

Can You Take Too Much Vitamin D?

While vitamin D is essential, too much of it can be harmful. Excessive vitamin D intake can cause high calcium levels in the blood, leading to:

• Nausea and vomiting
• Weakness and fatigue
• Kidney problems
• Bone pain

The upper limit for vitamin D intake is 4,000 IU (100 mcg) per day for adults. It’s always best to consult a doctor before taking high-dose supplements.

Conclusion:

Getting enough vitamin D is essential for bone health, immune function, and overall well-being. The best way to obtain vitamin D is through a combination of sunlight, food, and supplements. Spending time outdoors, eating vitamin D-rich foods, and taking supplements when necessary can help maintain healthy levels.