What Vitamin Do We Get From Sunlight?

Sunlight and Your Body

Sunlight gives off rays that can actually reach deep into your skin, all the way from the surface down to the inner layers where nerves and blood vessels are. A little sun exposure can be really good for you—it helps your body produce vitamin D and supports your overall health. But too much sun? That can cause sunburn, skin damage, freckles, moles, and even increase your risk of skin cancer and eye damage.

The Vitamin Your Body Gets From the Sun

Vitamin D is the one your body makes when your skin is directly exposed to sunlight. Most people get at least some of their vitamin D this way. However, sunlight coming through windows or on cloudy days doesn't count—your skin needs actual direct exposure. Also, the darker your skin, the less vitamin D your body will produce from the same amount of sun.

If you usually stay out of the sun, wear sunscreen, or cover most of your skin with clothes, you'll need to get your vitamin D from food or supplements. The recommended daily amounts assume you'll get at least a little sun exposure.

How Much Sun Do You Need?

For most people, just showing your hands, face, arms, and legs to the sun two to three times a week—about a quarter of the time it would take you to start burning—is enough to help your body make and store vitamin D. Your ideal sun exposure time depends on things like:

• Your age
• The season
• The time of day

There’s no perfect formula for how long to stay in the sun, but the World Health Organization suggests that getting about 5 to 15 minutes of sunlight on your arms, face, and hands a few times a week should do the trick. If you're going to be out longer than that, it's smart to put on sunscreen to protect your skin from damage.

Why Vitamin D Matters

Vitamin D is essential for keeping your body healthy. Here's why it's important:

• Bone health: It helps regulate calcium and phosphorus—two key minerals for strong bones. Your body also needs vitamin D to absorb calcium from food and recycle it through the kidneys.
• Lower diabetes risk: Low vitamin D levels have been linked to a higher risk of type 2 diabetes, as it can affect insulin release and how your body handles glucose.
• Healthy babies: Babies with low vitamin D might be more likely to develop issues like asthma, eczema, or other skin problems.
• Healthier pregnancies: Not getting enough vitamin D while pregnant can increase the risk of complications like preeclampsia, gestational diabetes, or the need for a C-section.
• Lower cancer risk: Vitamin D helps regulate cell growth and communication. Some studies suggest the active form of vitamin D (calcitriol) may slow cancer development by reducing blood supply to tumors and increasing cancer cell death.

Signs and Risks of Vitamin D Deficiency

Vitamin D deficiency is super common—over a billion people worldwide don't get enough. Low levels can raise your risk for several health issues, including:

• Obesity
• Type 2 diabetes
• High blood pressure
• Depression
• Fibromyalgia
• Chronic fatigue syndrome
• Osteoporosis
• Neurodegenerative diseases like Alzheimer’s
• Cancers such as breast, prostate, and colon cancer
• Heart disease and stroke
• Autoimmune disorders
• Birth defects
• Gum disease

How to Prevent or Treat Vitamin D Deficiency

You can boost your vitamin D levels through a mix of methods:

• Eat vitamin D-rich foods: These include cod liver oil, fatty fish like salmon, tuna, swordfish, and sardines, as well as fortified foods like milk, orange juice, and cereal. You'll also find some in egg yolks, beef liver, and fortified dairy products—but diet alone usually isn’t enough.
• Get short amounts of sun: A little sunshine here and there goes a long way.
• Take vitamin D supplements: If you're not getting enough from food or sun, supplements can help. Just make sure to check with your doctor and get a blood test to find the right dosage for you.

Daily Recommended Amounts for Vitamin D