Water Soluble Vs Fat Soluble Vitamins (Know the difference and more)

water soluble vs fat soluble vitamins

Vitamins are organic compounds that are required in certain doses for human beings to live a healthy life. Vitamins are defined as organic compounds that are not produced in sufficient quantities by the body and must therefore be supplemented through diet. The one (sort of) exception to this would be Vitamin D, which is only required by people who do not get enough sunlight. There are 13 vitamins that we require in our diet, and they are split into two types. Water soluble vitamins vs Fat Soluble Vitamins.

Water Soluble Vs Fat Soluble Vitamins

The first type is water soluble (vitamin C and the B vitamins) and the second type is fat soluble (vitamins A, K, E, and D). In this article we are going to take a look at the differences between the two types of vitamin, how they act within the body, and we’ll also take a look at what the benefits of taking them, and the dangers of taking too much of them are.

Vitamin Type Chart

Fat Soluble VitaminsWater Soluble Vitamins
Vitamin A (Retinol)Vitamin C (Ascorbic Acid)
Vitamin KVitamin B1 (Thiamine)
Vitamin EVitamin B2 (Riboflavin)
Vitamin DVitamin B3 (Niacin)
Vitamin B5 (Pantothenic Acid)
Vitamin B6 (Pyridoxine)
Vitamin B7 (Biotin)
Vitamin B9 (Folates)
Vitamin B12 (Cyanocobalamin)


What Are The differences Between Water Soluble & Fat Soluble Vitamins?

There are several differences between water soluble and fat soluble vitamins, but first let’s define soluble. It means a substance that can be dissolved. So a fat soluble vitamin can be dissolved in fat, while a water soluble vitamin can be dissolved in water. So far, so good.

Fat Soluble Vitamins (A,E,K,D)

Because a fat soluble vitamin is dissolved in fat, it can be stored in the body. They are mostly stored in the liver, and in your fat cells (known as adipose tissue). Because they can be stored, they don’t need to be topped up every day. Because of this they are rarely taken as a supplement.

Fat soluble vitamins are absorbed in the small intestine, metabolized in cells, and then transferred to adipose tissue. Excess fat soluble vitamins are also sent to the liver. It is possible to overdose on fat soluble vitamins, but it takes a huge amount for this to happen. Overdosing can lead to hypervitaminosis. This is possible for all fat soluble vitamins, but vitamin K seems to have such a high upper limit that it’s virtually impossible to experience it.

Fat soluble vitamins need to be taken alongside dietary fats such as olive oil, butter, and nuts. It is often stated that when dietary fats are cooked (grilling a steak for example) the fat soluble vitamins are destroyed. This is incorrect, they may be diminished but it is still possible to get some of them. How you cook them also makes a difference.

People who drop their body fat levels down to ridiculously low levels (usually bodybuilders, athletes, or people with eating disorders) can become deficient in fat soluble vitamins, because they have little adipose tissue to store it.

Water Soluble Vitamins (C, B1,B2,B3,B5,B6,B7,B9,B12)

Water soluble vitamins are dissolved in water and are not able to be stored in water, because of this they need to be topped up on a daily basis. Once the vitamin has been dissolved it travels round the body and delivers help where needed. After that it is excreted via the kidneys and leaves your body through urine.

If you are diabetic, or if you have drunk a lot of a diuretic such as alcohol, you will require a top up of water soluble vitamins, because so much is excreted through urine. This is one of the reasons why people are advised to increase vitamin c after a hangover.

Because water soluble vitamins aren’t stored in the body hence it is a lot easier to become deficient in them. Though this is becoming rarer, particularly in Western countries, it is still possible to get mild forms of scurvy from a lack of vitamin c, anemia from a lack of vitamin B6. It is also more difficult to overdose on them, though taking too much of a supplement can be toxic for your body.

Main Differences

Below is a quick and simplified table listing the main differences between fat soluble and water soluble vitamins.

Fat Soluble VitaminsWater Soluble Vitamins
·  Dissolved in fats  (lipids)

·  Stored in adipose tissue and the liver

·  Hard to become deficient in

·  Easy to overdose on

·  Dissolved in water

·  Not stored in the body

·  Easy to become deficient in

·  Difficult to overdose on (unless you take too many supplements)

Vitamins You Should Consider Supplementing With

Thanks to improved diet, the need for supplementation of vitamins is getting lower and lower. But there are still people who could benefit from certain vitamin supplements. Most of these are water soluble supplements (due to them not being stored in adipose tissue or the liver) but vitamin D – a fat soluble vitamin, can also be required by some.

  • Vegetarians and vegans should consider taking Vitamin B12 as a meat-free diet is going to be deficient in it.
  • Vegetarians and vegans may also be deficient in Vitamin B6, though it can be found in spinach and in fortified cereal.

  • Women who are pregnant might want to consider taking Folic Acid (Vitamin B7) as optimal folic acid levels can help develop your baby’s nervous system.

  • Niacin can be effective in helping you train harder in the gym, so is a useful supplement for that reason, otherwise it is rarely required as a supplement.


  • Vitamin D should be supplemented by people who don’t see a lot of the sun, it is particularly important for people with darker skin pigmentation who live in less sunny locations. This is because paler skin has less melanin and can therefore absorb more sunshine.

Final Thoughts

Hopefully by now you are aware of the differences between fat soluble and water soluble vitamins. When it comes to your diet it is vitally important that you consume sufficient quantities of both but you may need to pay more attention to your water soluble vitamin intake due to their lack of storage in the body.

If you are a bodybuilder of fitness lover and you are attempting to drop your body fat levels down as low as possible, then you should consider increasing your fat soluble vitamin intake, as your storage options will have reduced. But regular people should not have to worry about that.