We all need vitamin D, not only to live but to help prevent a variety of medical conditions and diseases including osteoporosis, depression, brain functioning problems, bowel inflammation and related issues. If people exposed their skin to daily sunlight there would be no need for a dietary or supplementary intake, however as our skin ages, consumption is more and more important as skin becomes less able to react to sunlight.
Our current European recommendation is to consume 5μg of vitamin D3 a day, however the new draft from the UK Scientific Advisory Committee on Nutrition guidelines suggest that everyone should take 10μg as a supplement every day, that’s 400IU of vitamin D3. It is possible to overdose and people should not exceed around 10,000 IU per day.
Although supplements supply a guaranteed whack of vitamin D, other sources that are promoted most frequently are fish because of their beneficial oils. Does anyone really know how much is in a fish and what fish to choose though?
Fish and fish products are regarded as the major dietary source of vitamin D. National food composition databases show values in the range of 0 to over 300 μg/kg of fish and fish products. A fish liver has the highest content with some as high as 1200 μg/kg of vitamin D.
The highest non liver amounts were found in fresh eel and shiokara, a Japanese fish product. The lowest are seen in highly processed fish. The vitamin D-3 content of the frozen fish and fish products ranged between <2 (shrimp) and 196 μg/kg (roe of vendace)
Contrary to general belief, vitamin D content may depend on the diet (i.e., the vitamin D-3 content of zooplankton and there is no significant correlation between fat and vitamin D content of fish ie it doesn’t matter how ‘oily’ the fish is!
So how much fish would you need every day to get the newly recommended 10 μg /400IU extra vitamin D3 per day?
- ½ tsp codliver oil
- 1.5 ounces of pink canned salmon
- 2 ounces of cooked fresh swordfish
- 2 ounces of fresh mackerel
- 2.5 ounces of rainbow trout
- 3 ounces of fresh sockeye salmon
- 6 ounces of canned tuna, drained
- Over 8 ounces of cod
- 17 sardines, canned in oil and drained
So have a look at the above and you’ll see it’s quite hard and also expensive to attain extra vitamin D! This is probably why the government state a supplement and not food!