Sunlight and Body Heat Make Vitamin D Inside Your Skin

Many people don’t get enough vitamin D in their food. They still get enough vitamin D, because ultraviolet radiation creates it—usually.

Source: Sunlight and Body Heat Make Vitamin D Inside Your Skin

If you’re as fair-skinned as the average northern European, you only need about 20 minutes per day.  All you have to show is an area of skin about the size of your face.

Without vitamin D from sunlight exposure, lactose assists with the use of calcium. So, cultures with easy access to leafy greens plus sunlight or fish, calcium is taken care of and milk has no advantage. Cultures without access to leafy greens, sunlight or seafood need dairy either as a source of calcium, lactose, or both.  You can read more about it in a previous post.

Why Your Fitness App Can’t Tell If You Have a Vitamin Deficiency

Diet tracking tools often include data about the vitamins and minerals you are (or aren’t) getting. While it’s fine to use that as motivation to eat a few extra veggies, you shouldn’t jump to the conclusion that you have a vitamin deficiency or need megadose supplements. Here’s why.

Source: Why Your Fitness App Can’t Tell If You Have a Vitamin Deficiency

Add to the fact that some food labels could be overestimating calorie counts…  And doctors might not be the best nutritional resource.  But blood tests are a good place to start.  Something else I learnt recently was that a nutritionist (like accountant) is generally not subject to professional regulation – a dietician is.  A dietician can be a nutritionist, but a nutritionist doesn’t mean they are a dietician.  The distinction can be regional – you’ll have to investigate for yourself to know what is what in your local area.

The part about the Reference Daily Intake (RDI) points out that though I mention the Daily Value (DV) when talking about how much vitamin K is in a given food, that value might be more (or less) than you need or want.