1. Significance and sources of folate
Domina Petric, MD

2. Significance
Widely distributed among foods, particularly those of plant foliar origin, this abundant vitamin is underconsumed by people whose food habits do not emphasize plant foods.
It is intimately related in function with vitamins B12 and B6.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

3. Significance
Folate deficiency is an important problem in many parts of the world, particularly where there is poverty and malnutrition.
It is an important cause of anemia, second only to nutritional iron deficiency.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

4. Significance
Folate has an important role in the etiology of homocysteinemia, cancer and birth defects.
High-level supplements of folate can mask the macrocytic anemia of vitamin B12 deficiency, which will lead to neuropathy if not corrected.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

5. Distribution in foods
Folates (folyl polyglutamates) occur in a wide variety of foods of both plant and animal origin.
Liver, mushrooms and green, leafy vegetables are rich sources of folate.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

6. Dairy products and other
Folate μg/100 g
Milk
5-12
Cheese 20
Other
Eggs 70
Brewers´ yeast
1500
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

7. Meats Meat Folate μg/100 g Beef 5-18 Beef liver 140-1070 Chicken liver
1810
Tuna 15
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

8. Cereals Cereal Folate μg/100 g Barley 15 Corn 35 Polished rice
Unpolished rice 25
Whole wheat
30-55
Wheat bran 80
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

9. Vegetables Vegetable Folate μg/100 g Asparagus 70-175 Beans 70
Broccoli
180
Brussel sprouts
90-175
Cabbage
15-45
Cauliflower
55-120
Peas 90
Soybeans
360
Spinach
50-190
Tomatoes
5-30
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

10. Fruits Fruit Folate μg/100 g Apples 5 Bananas 30 Oranges 25
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

11. Stability
Most folates in foods are easily oxidized and are unstable to oxidation under aerobic conditions of storage and processing.
Under such conditions (especially in the added presence of heat, light and/or metal ions), FH4 derivatives can readily be oxidized to the corresponding derivatives of dihydrofolic acid (FH2) or folic acid, some of which can react further to yield physiologically inactive compounds.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

12. Stability
Substantial losses in the folate contents of food can occur as the result of leaching in cooking water when boiling: losses of total folates of 22% for asparagus and 84% for cauliflower.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

13. Folate vitamers vary in biopotency.
Bioavailiability
Factors that affect the biologic availability of food folates are:
Antifolates in the diet
Folates can bind to the food matrices. Many foods contain inhibitors of the intestinal brush border folate conjugase and/or folate transport.
Inherent characteristics of various folates
Folate vitamers vary in biopotency.
Nutritional status of the host
Deficiencies of iron and vitamin C status are associated with impaired utilization of dietary folate.
November 16, 2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

14. Literature
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
November 16, 2018