What Vitamin to Take if You Don't Get Enough Sunlight? (It's Vitamin D)

December 18, 2025 •

4 min read

It's estimated that nearly half of the world's population may be vitamin D deficient, often due to insufficient sun exposure. If you don't get enough sunlight, it's essential to understand that vitamin D is the key nutrient you need to acquire from alternative sources to support your overall health.

Quick Summary

Limited sun exposure can lead to a deficiency in vitamin D, a vital nutrient for bone health and immune function. Learn about supplementation options, dietary sources, and risk factors to maintain adequate levels year-round.

Key Points

Vitamin D is the Primary Focus: If you don't get enough sunlight, the key nutrient to consider is vitamin D, often called the "sunshine vitamin".
Supplements Can Be Helpful: Vitamin D supplements, particularly the D3 form, can be effective for supporting sufficient levels when sun exposure is limited.
Food Can Contribute, But May Not Be Enough: While fatty fish, egg yolks, and fortified foods contain vitamin D, it may be challenging to get enough from diet alone to fully compensate for a lack of sun.
Deficiency Can Cause Fatigue and Mood Changes: Potential signs of low vitamin D levels include fatigue, muscle weakness, bone pain, and depressed mood.
Appropriate Intake is Key: Discussing appropriate intake with a healthcare provider is important.
Consult a Professional: It is crucial to consult a healthcare provider to check your vitamin D levels and discuss suitable strategies for you.

Why Vitamin D is Crucial When Sun Exposure is Low

When your skin is exposed to sunlight, it naturally synthesizes vitamin D, earning it the nickname "the sunshine vitamin". However, many factors can limit this natural process, such as living in northern latitudes, spending significant time indoors, having darker skin pigmentation, or simply avoiding the sun for health reasons. When this happens, your body's vitamin D levels can drop, leading to a deficiency that affects everything from your bones to your mood.

The Role of Vitamin D in Your Body

Vitamin D is actually a fat-soluble prohormone that is crucial for several physiological processes. It helps regulate the absorption of calcium and phosphorus, which are essential for developing and maintaining strong, healthy bones. Without enough vitamin D, your bones can become thin, brittle, or misshapen, increasing the risk of conditions like osteomalacia in adults and rickets in children. Beyond bone health, vitamin D also plays a significant role in modulating immune function, controlling inflammation, and even regulating mood. Low vitamin D levels have been linked to an increased risk of infections, autoimmune diseases, and depression.

How to Support Your Vitamin D Intake

If you don't get enough sunlight, considering supplements is one effective way to help maintain adequate vitamin D levels. The two main forms found are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Most evidence suggests that vitamin D3 is more effective at raising and maintaining overall vitamin D levels in the blood.

Considering Supplementation: Discussing supplementation with a healthcare provider can help determine if it's an appropriate strategy for you.
Choosing a Supplement: Look for a high-quality supplement that has been independently tested for purity and quality by a third party, such as USP or ConsumerLab.com.
Important Note: It is possible to take too much vitamin D, which can cause excessive calcium buildup in the blood (hypercalcemia). Always consult a healthcare provider to determine an appropriate approach for you.

Dietary Sources of Vitamin D

While few foods are naturally rich in vitamin D, incorporating specific items into your diet can help boost your intake. Food alone is often not enough to compensate for a lack of sunlight, but it can make a significant contribution.

Natural Food Sources

Fatty fish: Salmon, mackerel, sardines, and tuna
Fish liver oils: Cod liver oil is a prime example
Egg yolks
Beef liver
Mushrooms: Certain types, like portabella, can produce vitamin D when exposed to UV light

Fortified Foods

Milk (cow, soy, almond, oat)
Ready-to-eat breakfast cereals
Orange juice
Yogurt
Margarine

Factors Affecting Vitamin D Production from Sunlight

It's worth noting that relying on sun exposure alone can be unreliable for many individuals due to various factors. This is why considering alternative methods to support vitamin D levels is so important.

Comparison: Sunlight vs. Other Sources for Vitamin D


Feature	Sunlight Exposure	Supplements/Fortified Foods
Availability	Seasonal and geographic restrictions (winter, high latitudes). Affected by time of day, weather, pollution.	Year-round and widely available.
Contribution to Levels	Unreliable; varies based on skin type, age, and amount of skin exposed. Risk of sunburn with overexposure.	Can provide a consistent contribution. Can be used to address deficiency under guidance.
Safety	Excessive exposure carries a risk of sunburn, eye damage, and skin cancer.	Risk of toxicity (hypercalcemia) with excessive intake. Generally safe within recommended approaches.
Skin Type Impact	Darker skin requires significantly more sun exposure to produce the same amount of vitamin D.	No impact on absorption.
Convenience	Requires time outdoors, which may not be feasible due to lifestyle, location, or health.	Can be easily incorporated into a daily routine, regardless of external factors.

Potential Health Consequences of a Deficiency

If you consistently lack vitamin D, either from the sun or other sources, you may experience subtle symptoms that can develop into more serious health problems over time. Potential signs of deficiency include:

Persistent fatigue and low energy
Bone and joint pain, particularly in the back
Muscle weakness, aches, or cramps
Depressed mood or mood swings
Impaired wound healing
Frequent illness or infection
Hair thinning or loss
Bone loss, leading to osteoporosis

While these symptoms can overlap with other conditions, consulting a doctor for a simple blood test can help determine if a vitamin D deficiency is the root cause.

Conclusion

For those with limited sun exposure, vitamin D is the essential nutrient to focus on through dietary intake and other means. While sun exposure is the body's natural method of production, factors such as geography, season, and lifestyle can make it an unreliable source. To help ensure adequate levels for optimal bone health, immune function, and mood regulation, incorporating approaches like vitamin D3 supplements, along with fortified foods and natural dietary sources like fatty fish, is a practical strategy. Always consult with a healthcare professional before beginning any new supplement regimen to determine an appropriate approach for your individual needs. By being proactive, you can effectively manage your vitamin D intake and support your health, regardless of how much time you spend in the sun.

This article is for informational purposes only and does not constitute medical advice. For personalized recommendations, please consult a qualified healthcare provider.

Frequently Asked Questions

Vitamin D3 (cholecalciferol) is often considered the more effective form of vitamin D for raising and maintaining blood levels compared to vitamin D2. For those avoiding animal products, vegan D3 from lichen is also available.

It is very difficult to get enough vitamin D from food alone to compensate for a lack of sun exposure, as very few foods are naturally rich in it. This is why other strategies are often necessary for those with limited sun exposure.

Symptoms of a deficiency are often subtle and include fatigue, bone pain, muscle weakness, and mood changes. A simple blood test from your doctor is the most reliable way to confirm your vitamin D levels.

Determining an appropriate daily intake is best done in consultation with a healthcare professional, as individual needs can vary.

Yes, taking excessively high amounts of vitamin D supplements over a long period can lead to vitamin D toxicity (hypercalcemia), which can cause weakness, nausea, and potentially damage the kidneys or heart. Always stay within recommended guidelines unless advised otherwise by a doctor.

Fortified foods, such as milk, cereals, and orange juice, can contribute to your vitamin D intake, but they alone are unlikely to provide a sufficient amount to fully address a lack of sun exposure. They can be a helpful part of an overall strategy.

Yes, sunscreen with an SPF of 8 or higher can block the UV-B rays needed for your skin to produce vitamin D. However, experts still recommend using sunscreen to help prevent skin cancer, highlighting the need for considering alternative sources of vitamin D.