Approximately 75% of Americans are deficient in Vitamin D.
Inadequate levels of Vitamin D lead to:
1. Weak Bones
2. Weak Muscles
3. Weakened Immune System
Our bodies can make vitamin D from the sunlight, but this reaction can be stopped.
1. Sunscreen blocks Vitamin D conversion.
2. Windows also block Vitamin D conversion.
3. Height of the sun in the sky affects the conversion. Vitamin D production is highest between 10am & 3pm.
4. Time of year also affects the conversion. Where we live, vitamin D can only be made during the months of March through September.
We should aim for 1500—2000 IU of vitamin D daily.
1. Food is not a great source of vitamin D, but try to select foods that have vitamin D.
2. Supplements will be the easiest way to get vitamin D.
| Food | Amount of Vitamin D |
| 3.5 oz Wild Salmon | 980 IU |
| 3.5 oz Farm-Raised Salmon | 250 IU |
| 8oz Milk | 100 IU |
| Whole Egg (Vitamin D is in the yolk) | 18 IU |
Bottom Line: Still use sunscreen to protect your skin, but make sure you take your multivitamin and vitamin D daily.
© Randy Bird, MS, RD, CSSD, CSCS and Randy Bird Sports Nutrition, 2010.
Randy Bird Sports Nutrition 
Vitamin d deficiency has been linked to more than 20 (TWENTY!) different diseases and ailments. Science in recent years has confirmed that of all vitamins, this one is by far the most important.