Medically Reviewed

What are Water Soluble Vitamins? (And Why it Matters for You)

As a family, vitamins come in two classes: water-soluble and fat-soluble. The difference is how the vitamin behaves within the body.

The body needs water-soluble vitamins for many of its most critical functions. What is a water-soluble vitamin, anyways? It’s a particular class of vitamins. As a family, vitamins can be broken down into two categories: water-soluble and fat-soluble. The differentiation between the two comes from the way the vitamin behaves within the body. According to HealthLink BC, water-soluble vitamins travel throughout the body without restriction.

Ideally, the body would take in these water-soluble vitamins, frequently, and in small amounts. With that said, water-soluble vitamins are a lot less likely to reach levels that are toxic than fat-soluble vitamins. When the body has too much of a water-soluble vitamin, our kidneys excrete the excess amounts. However, if consumed in very high quantities over a long period of time, damage can still be done to the body.

A balanced diet normally provides all of the water-soluble vitamins you need. However, given that many individuals do not have a perfectly balanced diet, dietary supplements are often required to span the gap. This is especially true for vegetarians and vegans who often are missing vitamins because their diet forgoes many, or all, animal products.

What are the functions of water-soluble vitamins?

Every water-soluble vitamins functions differently and can be found in different foods. Many of them are used for the overall function of metabolism within the body, while others are used for supporting major bodily functions such as creating new cells or aiding in the absorption of other nutrients.

Vitamin C - or ascorbic acid aids in energy metabolism as well as boosting the immune system. It also helps with the body’s absorption of iron. It is only found in vegetables and fruits, most notably citrus fruits. It can also be found in a variety of vegetables, mostly those that come from the cabbage family. Once upon a time sailors and voyagers would suffer from scurvy when they were on the ocean for vast stretches of time. This is because they didn’t get enough vitamin C.

Thiamine is crucial to nerve function and for energy metabolism. It is found in all foods that have a nutritional value to them and it is usually included in a moderate amount. Those foods include whole-grain cereals and breads, nuts, seeds, pork and legumes.

Riboflavin is also used for energy metabolism as well as for the overall health of skin and eyes. It can be found in whole-grain breads and cereals, milk products and green vegetables. It can also affect the metabolism of other vitamins such as folate, iron, niacin, and vitamin B6.

Niacin is another vitamin needed for energy metabolism. It also aids the digestive system and nervous system and keeps skin healthy. You can find niacin in a variety of foods including fish, meat, whole grain cereals and breads, vegetables, poultry, and peanut butter. In fact, vegetables have the largest concentration of niacin, especially asparagus, leafy greens, and mushrooms. Therefore, vegetarians and vegans can rest more easily about their niacin levels!

Folic Acid is used to produce new cells within the body, namely cells in our nails, skin and hair. New cells in these and other areas are created every day. Folic acid is mostly found in fortified foods including pasta, breakfast cereals, bread and rice. Folic acid, which is the synthetic form of vitamin folate, is an even more crucial ingredient in the diet of women, particularly those who are pregnant or trying to conceive.

For those women who are pregnant, folic acid helps reduce the risk of major birth defects, including spina bifida and anencephaly. The Centers for Disease Control and Prevention recommends that women who are of reproductive age get 400 mcg of the vitamin every day.

Pantothenic acid can be found in virtually all animal- and plant-based foods. The only difference lies in the amount included in each. Those that contain the most include organ meats, some vegetables, beef, whole grains, and chicken. Like other water-soluble vitamins, pantothenic acid is primarily used by the body for energy metabolism.

Pyridozine (Vitamin B6) helps the body with metabolism and with the production of red blood cells. It can be found in many animal products such as poultry, meat and fish, but is also present in fruits and vegetables.

Vitamin B12 (Cobalamin) is crucial to the function of nerves within the body and the production of new cells. It can be found only in animal products, including poultry, seafood, milk products, eggs, meat, and milk.

Biotin aids in the metabolism of glucose, amino acids, and fatty acids. Biotin is found in most foods in varying concentrations and is also produced by the body itself within the bacteria of the intestinal tract.

Water-soluble vitamins to consider taking for metabolism:

Water-soluble vitamins include the following:

  • Vitamin C
  • B-Complex Vitamins (8):
    • Thiamin (B1)
    • Riboflavin (B2)
    • Niacin (B3)
    • Pyridoxine (B6)
    • Folic Acid/ Folate
    • Cobalamin (B12)
    • Pantothenic Acid
    • Biotin

Is vitamin D water-soluble?

No. Vitamin D is a fat-soluble vitamin. It can be found in fatty fish, fortified margarine, liver, fortified milk, and egg yolks. If the body is exposed to sunlight, it can make its own vitamin D through the skin. The vitamin is stored in bones and is critical for properly absorbing calcium.

Is vitamin C water-soluble?

Vitamin C, or ascorbic acid, is water-soluble. This vitamin is only found in vegetables and fruits. Fruits and vegetables with the densest vitamin C concentrations include citrus fruits, cantaloupe, peppers, strawberries, cabbage family vegetables, papayas, kiwi, potatoes, mangoes, lettuce, and tomatoes.

Vitamin C functions as an antioxidant in the body and is crucial for the immune system, according to the Academy of Nutrition and Dietetics. It also helps with the body’s ability to absorb iron.

Are B vitamins water-soluble?

B-Complex vitamins, similar to vitamin C, are not stored in the body. Instead, they must be replenished each day. B Vitamins can be found in a number of different foods and food groups including poultry, fish, eggs, cereal grains, milk, fresh vegetables, and meat.

A total of eight of the water-soluble vitamins are from the vitamin B group. These include riboflavin, thiamin, niacin, folate, vitamin B6, biotin, pantothenic acid and vitamin B12. These vitamins help the body turn food into energy and are critical for the nervous system, healthy skin, the formation of red blood cells, a normal healthy appetite and good vision.

Do you have a water-soluble vitamin deficiency?

The signs of water-soluble vitamin deficiency are varied, given that deficiency symptoms vary by vitamin. For example, a deficiency in vitamin C can manifest with easy bruising, wounds that take forever to heal, and swollen joints.

The symptoms of a vitamin B complex deficiency manifest according to the vitamin as well. If you have a deficiency in B1, you might experience depression or low appetite, whereas with vitamin B2, your mouth might be sore, and your lips cracked. With a vitamin B3 deficiency, you could experience mental confusion or diarrhea. A deficiency in vitamin B6 might showcase anemia or damage to the nerves. A B12 deficiency results in anemia as well, but can also be accompanied by the signs of infertility.

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