Does Water Have Vitamin D in It? The Surprising Truth

December 15, 2025 •

4 min read

According to the National Institutes of Health, a significant portion of the global population has inadequate vitamin D levels. This widespread issue drives many to question every possible source, leading to the common inquiry: does water have vitamin D in it?

Quick Summary

This article explains why water does not naturally contain vitamin D by exploring the difference between fat-soluble and water-soluble vitamins. It identifies the real sources of vitamin D, including sun exposure, fortified foods, and supplements.

Key Points

No Natural Vitamin D: Water does not naturally contain vitamin D because it is a fat-soluble vitamin that requires fat for absorption.
Fat-Soluble vs. Water-Soluble: Vitamin D belongs to the fat-soluble group (A, D, E, K), which is stored in the body's fat and liver, unlike water-soluble vitamins that are not stored.
Sunlight is Key: The body primarily synthesizes its own vitamin D from cholesterol in the skin when exposed to UVB rays from the sun.
Fortification is Possible: While plain water lacks it, some bottled waters are fortified with vitamin D, making them a viable source of the nutrient.
Dietary Sources: Natural dietary sources of vitamin D include oily fish, egg yolks, and fortified foods like milk, cereals, and certain juices.
Stay Hydrated, Separately: It is important to remember that water's main role is hydration; vitamin D intake should be addressed through appropriate sun exposure, diet, or supplements.

The Fundamental Difference: Fat-Soluble vs. Water-Soluble Vitamins

To understand why vitamin D is not present in plain water, it's crucial to first differentiate between fat-soluble and water-soluble vitamins. This classification determines how the body absorbs, stores, and utilizes these vital nutrients.

Fat-Soluble Vitamins: These include vitamins A, D, E, and K. As their name suggests, they dissolve in fat and are absorbed best when consumed with a source of dietary fat. The body stores these vitamins in its fatty tissues and liver for later use.
Water-Soluble Vitamins: This category includes vitamin C and the B vitamins. They dissolve in water and are not stored in the body in large amounts. If you consume more than your body needs, the excess is typically flushed out through urine.

Why Vitamin D Isn't Found in Plain Water

Vitamin D is a classic example of a fat-soluble vitamin. It is primarily synthesized in the skin upon exposure to ultraviolet-B (UVB) rays from sunlight. This process requires a precursor molecule derived from cholesterol in the skin. Water, being a simple compound of hydrogen and oxygen (H2O), contains no fat or cholesterol. Therefore, there is no biochemical mechanism for it to naturally contain or produce vitamin D. Furthermore, because vitamin D is not water-soluble, it cannot dissolve in water and remain stable in a standard liquid solution.

The Real Sources of Vitamin D

Since plain water is not a viable source, you must turn to other, more reliable methods to ensure adequate vitamin D intake. The main sources are sunlight, diet, and supplementation.

Sunlight Exposure: The most direct and efficient way to obtain vitamin D is through sun exposure. When UVB rays hit the skin, it triggers the synthesis of vitamin D3. The amount produced depends on factors like time of day, season, and skin pigmentation.
Dietary Sources: A limited number of foods naturally contain significant amounts of vitamin D. These include oily fish (such as salmon and mackerel), cod liver oil, beef liver, and egg yolks.
Fortified Foods: To combat widespread deficiency, many food products are fortified with vitamin D, including milk, some breakfast cereals, yogurt, orange juice, and plant-based milk alternatives.
Supplements: Vitamin D supplements are widely available in D2 and D3 forms and are an effective way to meet your daily needs, especially when sunlight exposure is limited. Taking supplements with a meal containing fat can enhance absorption.

The Exception: Fortified Water

While plain water lacks vitamin D, fortified bottled water is a growing market exception. Some manufacturers add vitamins, including D, to their products to create a nutrient-enhanced beverage. Studies have shown that vitamin D added to water and milk is absorbed more effectively than when added to juice. This makes fortified water a viable option for those looking to increase their vitamin D intake, though it is not a natural property of water itself.

Comparison of Vitamin D Sources


Source	Vitamin D Present	How It Works
Sunlight	Yes	UV rays trigger skin synthesis.
Oily Fish / Egg Yolks	Yes (Naturally)	Present in the fatty components of the food.
Fortified Milk	Yes (Added)	Vitamin D is added to enhance nutritional value.
Fortified Water	Yes (Added)	The vitamin is added during manufacturing.
Regular Water	No	Lacks the necessary fat/cholesterol for vitamin D.

The Role of Water for Overall Health

While water is not a source of vitamin D, it is fundamental for overall health and the proper functioning of the body's systems. Dehydration can lead to numerous health issues, affecting everything from energy levels to cognitive function. It is essential to remember that hydration and nutrient intake are two separate, but equally important, components of a healthy lifestyle. Your water intake should focus on proper hydration, and you should obtain vitamin D from the reliable sources mentioned above.

Conclusion: Separating Fact from Fiction

In conclusion, the claim that water contains vitamin D is a myth. The biological and chemical properties of vitamin D, as a fat-soluble vitamin derived from sunlight or dietary fats, make it naturally impossible for it to exist in plain water. While fortified water products do exist and can be effective, they are a manufactured exception and not a natural source. Focus on safe sun exposure, a balanced diet rich in natural and fortified foods, and supplements if necessary to meet your vitamin D needs, while continuing to drink plenty of water for hydration. Learn more about vitamin D from the Harvard T.H. Chan School of Public Health.

Note: If you have concerns about your vitamin D levels, consult a healthcare professional for guidance and personalized advice.

Frequently Asked Questions

Vitamin D is not found in plain water because it is a fat-soluble vitamin, meaning it does not dissolve in water. It requires fat to be absorbed by the body and is produced through sun exposure or found in certain fatty foods.

No, you cannot get vitamin D from drinking tap water. Tap water is not a source of vitamin D, and no standard water purification processes add this vitamin to the supply.

Fat-soluble vitamins (A, D, E, K) dissolve in fat and are stored in the body's fatty tissues and liver. Water-soluble vitamins (C and B vitamins) dissolve in water and are not stored in large quantities, with any excess being excreted.

Yes, several drinks contain vitamin D. These are typically fortified beverages, such as milk, certain types of orange juice, plant-based milk alternatives, and specially manufactured vitamin-enhanced bottled waters.

When vitamin D is fortified into water, it is added in a way that allows for effective absorption. Research indicates that vitamin D fortification in water or milk is absorbed comparably well by the body, even without high fat content.

The best sources of vitamin D are exposure to sunlight, consuming oily fish (like salmon and mackerel), eating egg yolks, and drinking fortified products such as milk and certain juices.

No, drinking water exposed to the sun does not provide vitamin D. The vitamin is synthesized in the skin of living organisms in response to sun exposure, not in an inert substance like water.