Protein Supplementation Might Improve Body Composition During Weight Loss

As we get older, many of us tend to put on a few extra pounds of fat, while losing some of our muscle mass.  This gradual change in body composition has been reported to be associated with a loss of physical function as we age.  Most any sensible weight loss plan is a great way to get rid of those extra pounds of fat, but might not necessarily prevent a loss in muscle mass. 

A new weight loss research study presented at the 2010 Experimental Biology meeting explored the potential benefit of adding a protein supplement to an energy-restricted diet for supporting healthy weight loss and improved levels of fat-free mass (muscle, bone, etc.).  In this study, obese women with an average age of about 64 years were asked to follow a 1,500-calorie per day diet and randomly assigned to receive either (1) 50 grams of protein per day or (2) 50 grams of carbohydrates (maltodextrin) per day.  Changes in body fat, fat-free mass, and weight loss were measured after 6 months.  The weight loss researchers reported:

• Protein supplementation provided a greater loss of body fat (about 19%) than carbohydrate supplementation (about 8%).
• While not statistically significant, weight loss was slightly greater for protein supplementation (about 11% of body weight on average) than for carbohydrate supplementation (about 5% of body weight on average)
• Fat-free mass was only modestly reduced in both the protein and carbohydrate groups.
• Thigh fat under the skin was substantially reduced by protein supplementation compared to carbohydrate supplementation.

These new weight loss study results suggest that supplementing a low-calorie diet with protein might support better body fat loss, while also providing weight loss benefits and modest preservation of fat-free tissues.  The study abstract did not mention any exercise component of the diet program, which might be one reason that fat-free mass still decreased slightly in this study.  Combining exercise with a healthy diet plan might better preserve or possibly even improve muscle mass compared to a diet plan without exercise.  However, it is possible that this study did contain an exercise program that simply wasn't mentioned in the study summary.  Nonetheless, these results suggest some possible benefits of supplementing a healthy diet plan with a little extra protein.

Dr. Tabor's Diet plan includes soy protein and milk protein shakes and bars, which are a great way to make sure you are getting enough high quality protein while managing your weight. 

Vitamin D Might Support Normal Physical Function in Seniors

Over the last several years, research has shown that vitamin D appears to play an important role in many aspects of human health, including the maintenance of normal muscle health.  However, little research has looked at the role of vitamin D on physical function in older individuals.

A new vitamin D research study examined the potential association between vitamin D blood levels and leg function in nearly 3,000 individuals with an average age of 75 years.  For this study, researchers measured blood levels of vitamin D in the study volunteers and then asked them to perform a short battery of physical tasks, including walking 400 meters and knee strength tests.  The study investigators reported that:

• Volunteers with vitamin D blood levels greater than 75 nmol/L had higher overall physical performance scores compared to volunteers with low vitamin D levels (less than 50 nmol/L).
• Individuals with high vitamin D blood levels were able to walk at a faster speed than subjects with low vitamin D levels.
• Knee strength was not different between individuals with low or high vitamin D levels.

This is interesting research that adds to the growing body of evidence around the importance of vitamin D for normal human health.  This new research suggests that maintaining adequate vitamin D levels might help support normal muscle health as we get older.  However, it is important to remember that this study only looked at associations and was not able to determine cause and effect.  Therefore, it is possible that the better physical performance in individuals with higher vitamin D levels could be due to other things.  Nonetheless, insufficient levels of vitamin D can lead to a variety of chronic conditions, so it is important to make sure you get enough vitamin D each day.

While you can generally get all the vitamin D you need by spending time in the sun, you can also get vitamin D in the diet.  My milk protein bars and milk protein shakes provide 25 - 35% of most people's daily needs, making them a delicious and easy way to boost your vitamin D levels.