A recent study has found that insufficient levels of vitamin D in older adults doubles the risk of Alzheimer’s Disease. But it’s not just older folks, like me, who aren’t getting enough of the sunshine vitamin. Most kids don’t get enough either.
What is vitamin D? Why is it important? Why aren’t people getting enough? And what are its best food sources?
But first …
Vitamin D is not a vitamin
We’ve been taught that Vitamin D is the “bone vitamin”, but it is really more of a sun hormone. The word “vitamin” means “something my body needs that I can’t make, so I must get it from the food”. D hormone is instead, a chemical that we make on our skin from sun exposure. It is a hormone like thyroid, estrogen or testosterone. Using the proper word “hormone” reminds us that it affects multiple parts of the body and that it is not “extra”. It is essential to every cell in the body and it is not in the food. It is supplemented in milk but as a cup of milk has only 100 IU of vitamin D you would have to drink100 cups of milk a day to keep from being D deficient.
What else you need to know
1. Vitamin D is a fat soluble vitamin that is found in food but can also be manufactured by our body after exposure to sunshine’s UV rays. fat soluble means it needs a to be consumed together with a small amount of oil/butter/lard etc… to be effectively absorbed by your body.
2. Vitamin D’s job is to help the body absorb and regulate calcium and phosphorous levels in the body.
3. Without vitamin D, our bones don’t get enough calcium and bones become thin and brittle, or don’t develop properly if you’re still a growing child.
4. In the past most people got enough vitamin D just by being outdoors, but the industrial revolution and lifestyle changes it brought about have led to drastic reduction in this source for most people. Today, many people apply sunscreen for outings, thus reducing the vitamin D manufacturing capability of the body.
5. According to the National Institute of Health, anyone over the age of 1 needs 600 IU (International Units* ) of vitamin D. Seniors over the age of 70 need 800 IU.
Note:* 1 microgram of vitamin D = 40 IU.
6. In the past, vitamin D deficiencies led to skeletal diseases such as rickets. The US and other countries began fortifying milk with vitamin D as a public health measure, and pretty much eradicated these types of diseases.
7. Today virtually all milk sold in the US is fortified with 100 IU (International Units) of vitamin D per cup. Other products are also fortified with vitamin D. Examples include yogurts and breakfast cereals. Some sugary children’s cereals have jumped on the vitamin D fortification bandwagon, but they usually provide just 10% of the daily requirement while pumping your kids up with too much sugar.
8. The best food source of vitamin D is a teaspoon of cod liver oil (1,360 IU), but most people dread just the sound of that, not to mention the taste. Herring, sardines, salmon, and tuna are also good sources but usually do not supply enough of the vitamin.
9. Some nutrition experts therefore recommend vitamin D supplements, even if you are eating healthfully.
10. There are several forms of vitamin D: D1, D2, D3, D4, and D5, but the most relevant to nutrition are D2 (ergocalciferol) and D3 (cholecalciferol). When used in supplement pills, D2 is derived from yeast or fungus, while D3 is from animal sources.