(HealthNewsDigest.com) – OK, you are already confused after reading the title. Who knew there were two types of vitamin D and why does it matter? It does matter because we are learning that vitamin D2 may not have much impact on human health, whereas vitamin D3 can help balance your immune system and strengthen your defenses against viral infections such as Covid-19.
Many of us remember vitamin D as the sunshine vitamin. That is true because ultraviolet B (UVB) radiation from sunlight triggers the formation of vitamin D3 from a compound (7-dehydrocholestrol) found in your skin. Vitamin D3 can also be found in fatty fish, fish oil, liver, and egg yolk. The other form of the vitamin, D2, comes mainly from plant sources and foods fortified with the vitamin. In both cases there are few rich food sources. Couple this with the use of sunscreen, working indoors, living in areas with less sunlight, or having darker skin, and many people are lacking enough vitamin D.
To be sure that you get enough, most of us need to take a daily supplement and eat foods fortified with vitamin D. This is where the difference between D3 and D2 becomes more important. D3 should be your preferred supplement because this form of the vitamin is a key part of the immune system that provides a first line of defense against bacteria and viruses. A healthy vitamin D3 status may help to prevent viruses and bacteria from gaining a foothold in the body. Many experts feel low levels of vitamin D were a contributing factor to the severity of Covid-19 infections.
When you buy a vitamin D supplement, check the label to see if you are getting D3 (cholecalciferol). The US Institute of Medicine recommends a daily allowance of 600 to 800 IU (10 to 20 micrograms) but supplements commonly found in stores usually have 1,000 to 2,000 IU (25 to 50 micrograms). That level is perfectly fine, just be sure not to exceed the upper safe intake level of 4,000 IU (100 micrograms) daily. As with all things the dose makes the poison and vitamins are no different. The right amount is helpful but too much can cause problems. Vitamin D is a fat soluble vitamin, which means excess amounts of the vitamin are stored in your body’s fat cells and not easily excreted if unneeded. When you get vitamin D3 from sunlight, your skin will stop converting the sun’s rays into the vitamin if you have an ample amount in your body. When you take a supplement, you have to monitor the dose and keep it within a healthy range.
Vitamin D2 is the more common form found in fortified foods. The nutrition facts panel will not tell you which form of the vitamin is in the food, just the amount. Look at the ingredient list and if vitamin D3 is used it should be listed there. If no source for the vitamin is listed you can assume the brand is fortifying with vitamin D2. For example, Cheerios lists vitamin D3 under ingredients but Carnation Evaporated Milk does not list a source for the vitamin in the ingredient list so there is no way to know which form was used to fortify the milk. If you are taking a vitamin D3 supplement daily you don’t need to be too concerned about the source of the vitamin used to fortify the brand name foods you buy.
Bottom line on vitamin D:
It is needed in your body to support your immune system, help absorb calcium, and regulate bone growth.
Sunshine helps your body make vitamin D but we get too little from this source.
Fortified foods can be a good source but check the label to see if the brand is adding D3.
Taking a daily supplement of vitamin D3 is wise.
Jo-Ann Heslin, MA, RD, CDN is a registered dietitian and the author of 30 books. Available as eBooks from iTunes and Kindle/Amazon:
Diabetes Counter – the most up-to-date information on managing diabetes
Calorie Counter – a weight loss guide that won’t let you down
Protein Counter – put the latest protein recommendations to work for you
Healthy Wholefoods Counter – planet-friendly eating made easy
Complete Food Counter – food counts and nutrition information at your fingertips
Fat and Cholesterol Counter – newest approach to heart-healthy eating
Available in print from Gallery Books:
Most Complete Food Counter, 3rd Ed.
For more information on Jo-Ann and her books, go to: www.TheNutritionExperts.com.