Fat Soluble Vitamins
Fat soluble vitamins are critical to health and wellness--particularly reproductive health and wellness. Unfortunately, adequate intake of fat soluble vitamins is sorely lacking among modern peoples--especially by comparison to traditional societies. Average intake of fat soluble vitamins like vitamin A, vitamin D, vitamin E and vitamin K is inadequate at best and dangerously low at worst--even among health circles. Low-fat, no-fat and vegan diets are woefully lacking in fat soluble vitamins; however a diet based on traditional foods--those foods that nourished our ancestors through their evolution-- can naturally provide these vitamins.
Fat Soluble Vitamins: Where to get them?
Fat soluble vitamins are just that: they're capable of being dissolved in fat unlike other vitamins which are water soluble. In short, to reap the benefits of these vitamins you need to eat fat. And plenty of it. The higher quality the fat, the more likely it is to contain fat soluble vitamins like vitamin A, vitamin D, vitamin E and vitamin K.
Vitamin A
Vitamin A: What is it?
Vitamin A is a fat soluble vitamin that can be classified into retinols or carotenoids. These substances are metabolized by the body to form usable vitamin A.
Retinols--the vitamin A found in animal-source foods--require very little work by the body in order to convert it to true vitamin A. Retinols are sometimes referred to as pre-formed vitamin A or true vitamin A due to the fact that they require such little effort on the part of the body in order for it to be usable.
Carotenoids which include the very prevalent beta carotene are poorly converted by the body. For example, some studies indicate that the body requires as much as twenty-one times the amount of carotenoids to create the same amount of vitamin A is one part retinol. To add insult to injury many people, especially those suffering from thyroid disorders and small children, are even poorer converters. A 2001 study found that the conversion rate of carotenoids to true vitamin A is so poor as to render it nutritionally insignificant.
Vitamin A: Its Role in Health
Vitamin A, like other fat soluble vitamins, is critical to health. It is essential to growing children and to mothers and fathers who are trying to conceive. It promotes a healthy immune system, fertility, good vision and healthy skin. Vitamin A also plays a role in the health of the heart. Low maternal intake of vitamin A has been linked birth defects including cleft palate (see more about maternal intake of vitamin A and cleft palate).
Vitamin A: Whole & Traditional Food Sources
While beta-carotene is a great antioxidant and plays a very important role in overall health, if you're shooting for vitamin A make sure to get it from reliable sources like animal foods which are rich in retinol--that form of vitamin A that is most easily absorbed by the body.
Retinol in Micrograms per 100-gram serving.
- Calf Liver (21140 mcg per 100-gram serving)
- Goose Liver Pâté (1001 mcg per 100-gram serving)
- Fresh Butter (671 mcg per 100-gram serving)
- Fresh Tuna (655 mcg per 100-gram serving)
- Fresh Cream (405 mcg per 100-gram serving)
Vitamin D
Vitamin D: What is it?
Vitamin D is a group of fat-soluble vitamins. They are considered prohormones, or the precursors to hormones, and are essential to endocrine health. There are several forms of vitamin D, but the most common are ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3) which are known together as calciferol.
Vitamin D2 is not a truly natural form of the vitamin D. Vitamin D2 does not occur in any detectable quantities in humans; instead, it's produced in minute quantities in plants. Supplementary vitamin D2 is manufactured by subjecting fungus to ultraviolet radiation. As this process is considered "natural," supplementary vitamin D2 may be misleadingly labeled as "natural" even though that is not truly the case. Recent research indicates that vitamin D2 is linked to calcium malabsorption.
In a study on vitamin D2 published in the American Journal of Clinical Nutrition, researchers stated:
"These are officially regarded as equivalent and interchangeable (1-3). Although sunshine exposure and fish consumption provide vitamin D in the form of D3, a different bioactive, plant-derived form of vitamin D, named vitamin D2, was produced in the early 1920s through ultraviolet exposure of foods. This process was patented and licensed to pharmaceutical companies, which led to the development of a medicinal preparation of vitamin D2 ... Vitamin D2, or ergocalciferol, should not be regarded as a nutrient suitable for supplementation or fortification."
Vitamin D: Its Role in Health
Vitamin D is critical to bone health and immune system function. Vitamin D deficiency is actually fairly common, and is linked to high blood pressure, cancer, periodontal disease, osteoporosis and autoimmune disease.
Vitamin D: Whole & Traditional Food Sources
Raw, oily, ocean-going fish represent one of the best food sources of vitamin D. Many nutritionists also recommend pasteurized milk as a source for vitamin D; however, the vitamin D added to pasteurized milk is vitamin D2 and is best avoided.
IUs of Vitamin D per 100-gram serving.
- Sunlight.
- Mackerel Sashimi (360 IU)
- Raw Oysters (320 IU)
- Sardines (272 IU)
- Raw Pastured Egg Yolk (107 IU)
Vitamin E
Vitamin E: What is it?
Vitamin E refers to several nutrients called tocopherols. These are fat soluble vitamins. Of these tocopherols, alpha-tocopherol offers the highest bioavailability. While alpha-tocopherol seems to be the most active, beta-tocopherol, gamma-tocopherol and delta-tocopherol each play their complementary role. As with other fat soluble vitamins, avoid synthetic supplements.
Vitamin E: Its Role in Health
Vitamin E is a powerful antioxidant. This fat soluble vitamin is essential for cell health. It's remarkably effective in mitigating cardiovascular disease with protective effects for the entire circulatory system. Vitamin E also promotes healthy, clear skin. Due to its status as an antioxidant, it could prove helpful in the fight against cancer. Beyond that, it's critical for eye health and may mitigate the effects of cataracts.
Notable naturopathic physician, Ron Schmid has this to say about vitamin E in his book Traditional Foods Are Your Best Medicine:
"The absence of whole grains and liver, traditional foods rich in vitamin E, from the modern diet has resulted in widespread deficiencies. Much evidence demonstrates this has significantly contributed to the modern epidemic of heart disease and other problems."
Vitamin E: Whole & Traditional Food Sources
Nuts and seeds represent some of the most concentrated sources of vitamin E traditionally available, although vitamin E can be found in whole grains and some animal foods.
Mgs of Alpha-tocopherol per 100-gram serving.
- RawAlmonds (26 mg)
- Palm Kernel Oil (19 mg)
- Flaxseed Oil (17 mg)
- Raw Hazelnuts (17 mg)
- Wild Salmon Roe (7 mg)
Vitamin K
Vitamin K: What is it?
Vitamin K is a group of vitamins, notably vitamin K1 and vitamin K2. Vitamin K, like vitamins A, D and E, are fat soluble vitamins. Vitamin K1 and vitamin K2 are naturally occuring vitamins; however, there's a subset of vitamin K which include vitamin K3, K4, K5 all of which are synthetic vitamins.
Vitamin K2 is produced be beneficial bacteria that are naturally occurring in the intestinal tract of healthy people. Those with severely damaged guts, or who have been subjected to the consistent use of broad-spectrum antibiotics may lack these vital bacteria and therefore may suffer from poor vitamin K2 production.
Vitamin K: Its Role in Health
Vitamin K is essential for proper blood clotting. Vitamin K also supports bone health, even reducing post-menopausal bone loss among women. Interestingly, vitamin K may even prove effective in the fight against degenerative cognitive diseases like Alzheimer's Disease. Japanese studies indicate that vitamin K could play a very vital role in the treatment of cancers--particularly liver cancer.
Vitamin K: Whole & Traditional Food Sources
Leafy greens represent a great source of vitamin K, but take care to eat these greens with an accompanying wholesome fat.
Mcg of Vitamin K per 100-gram serving.
- Cooked Kale (882 mcg)
- Raw Swiss Chard (830 mcg)
- Dandelion Greens (778 mcg)
- Raw Radicchio (255 mcg)
- Miso (23 mcg)