Vitamin D, Muscle, and Fat

13 05 2010

Most people realize that vitamin D assists the body in absorbing calcium.  This assisting role helps the body have strong bones.  What most people don’t realize is that this role only represents 15% of what vitamin D does.  There are over 200 genes in our body that have vitamin D receptors.  This means that having adequate vitamin D levels allows our body to function correctly at the genetic level, enhancing many things from immune function to muscle strength.

A new study published in the Journal of Clinical Endocrinology and Metabolism looked at the relationship between vitamin D status and fat content of muscles.  Our muscles naturally store fat as an energy source.  But a higher muscle fat content is associated with lower levels of strength and performance.

This current study measured blood levels of vitamin D and, using a CT scan, measured the amount of fat in muscles.  What the researchers found was an inverse relationship between the two measurements.  The lowest vitamin D levels were associated with the highest amount of fat in the muscles.  A reasonable assumption is that vitamin D insufficiency is associated with a decrease in muscle strength.

I always encourage people to get their serum Vitamin D levels checked.  Once you know that number, you will know how much vitamin D is best for you to take.  I generally recommend between 1500 and 2000 IU per day.  It is very difficult to get this amount from food.  And although it is possible to get such a level from sun exposure, I don’t recommend forgoing sunscreen.  So personally, I take 2000 IU per day combined between my multivitamin and a vitamin D supplement.  I typically recommend the Nature Made brand to clients because they submit to strict quality testing by the United States Pharmacopeial; this way you know you are getting exactly what is on the label.

© Randy Bird, MS, RD, CSSD, CSCS and Randy Bird Sports Nutrition, 2010.


Vitamin D deficiency can make you weak…

21 04 2010

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.

What you eat can affect your joints…

16 04 2010

Maintaining and regenerating cartilage and synovial (joint) fluid helps to avoid frictional damage to your joints.

Adequate daily intake of protein and water can be essential to maintain good levels of synovial fluid.
1. For protein, get at least 0.5 gram per pound of body weight.
2. For water, get at least 0.5 ounces per pound of body weight.

Omega-3 Fatty Acids can help joints by reducing inflammation.
Good sources are:
Salmon, Tuna, Sardines, Fish Oil, Walnuts, Canola Oil, & Flaxseed.

Both vitamin D and vitamin C are important as well.
1. Eat a fruit or vegetable with every meal or snack.
2. Take your multivitamin daily.
3. During the Fall & Winter, take your vitamin D supplement daily.

Weight  | Protein (g/day) | Water (oz/day)
130 lbs  | 65—104 grams   | ≥ 65 ounces
160 lbs  | 80—128 grams   | ≥ 80 ounces
180 lbs  | 90—144 grams   | ≥ 90 ounces
200 lbs  | 100—160 grams | ≥ 100 ounces
220 lbs  | 110—176 grams | ≥ 110 ounces
250 lbs  | 125—200 grans  | ≥ 125 ounces
300 lbs  | 150—240 grams | ≥ 150 ounces

© Randy Bird, MS, RD, CSSD, CSCS and Randy Bird Sports Nutrition, 2010.