We take vitamins and supplements to support those we get from the food we eat and the sunlight we are exposed to. They are absorbed into the body in different ways and are excreted at different rates. In general terms, we can classify them as soluble in water or soluble in fat.
Water soluble vitamins
Water soluble vitamins are vitamins that dissolve in water and are easily absorbed into tissues for immediate use. Since they are not stored in the body, they must be regularly replenished in our diet.
Any excess water-soluble vitamins are rapidly excreted in the urine and rarely accumulate to toxic levels. However, certain types of water-soluble vitamins, such as vitamin C , can cause diarrhea if taken in excess.
Water soluble vitamins include the B complex group and vitamin C, each of which has the following health benefits:
- Vitamin B1 (thiamine) helps release energy from food and is important for maintaining the function of the nervous system.
- Vitamin B2 (riboflavin) contributes to good vision and healthy skin, and is also important in the conversion of the amino acid tryptophan to niacin.
- Vitamin B3 ( Niacin ) contributes to digestion, metabolism and normal enzyme function, and promotes healthy skin and nerves.
- Vitamin B5 (pantothenic acid) promotes metabolism and hormone production.
- Vitamin B6 (pyridoxine) promotes protein metabolism and the production of red blood cells, insulin, and hemoglobin.
- Vitamin B7 ( biotin ) helps release energy from carbohydrates and aids in the metabolism of fats, proteins, and carbohydrates from food.
- Vitamin B9 ( folic acid or folic acid ) also promotes protein metabolism and red blood cell formation and may reduce the risk of neural tube birth defects.
- Vitamin B12 ( cobalamin ) helps in the production of normal red blood cells and also supports the nervous system.
- Vitamin C (ascorbic acid) plays a central role in the absorption of iron and the synthesis of collagen . Helps in wound healing and bone formation while improving overall immune function .
Fat soluble vitamins
Fat-soluble vitamins are fat-soluble. They are absorbed by fat globules, which pass through the small intestine and are distributed throughout the body through the bloodstream.
Unlike water-soluble vitamins, excess fat-soluble vitamins are stored in the liver and adipose tissue for future use. They are most commonly found in high-fat foods and are best absorbed when eaten with fat .
Because fat-soluble vitamins are difficult to remove, they can build up to toxic levels if taken in excess. When a well-balanced diet is not likely to cause toxicity, an overdose of fat-soluble vitamin supplements can occur.
There are four types of fat-soluble vitamins, each with different benefits:
- Vitamin A is essential for the formation of bones, teeth and vision. Promotes immune and cellular function while maintaining normal bowel function.
- Vitamin D contributes to the development of teeth and bones by promoting the absorption and metabolism of phosphorus and calcium.
- Vitamin E is an antioxidant that helps fight infection and keeps red blood cells healthy.
- Vitamin K plays a central role in blood clotting and also supports bone health .
Frequently asked questions
The symptoms and side effects of fat-soluble vitamin toxicity differ by vitamin. They range from nausea and vomiting to stunted growth and birth defects.
Maximum allowable daily level of vitamin A supplements by age:
- Infants and children under 3 years: 300 mcg (mcg)
- Children 4-8: 900 mcg
- Teens 9-13: 1700 mcg
- Adolescents 14-18: 2,800 mcg
- Adults 10 to 70 years and older: 3,000 mcg.