According to a recent study published in the Journal of the Federation of American Societies for Experimental Biology (FASEB) (Pasiakos, September 2013) consuming more protein may protect you from losing muscle mass while trying to lose weight. Although a small study of only 39 men and women, the randomized, controlled trial showed a significant difference in muscle mass lost while on a weight loss diet between subjects who consumed the Recommended Daily Allowance (RDA) of protein (0.8 grams per kilogram of body weight) and those who consumed 2-3 times that amount. This means that those who ate more protein still lost weight, but lost less muscle and more fat in the process.
The 31-day study started off by dividing the subjects into three groups; group one ate a diet including the RDA for protein, 0.8g/kg; group two received a diet containing 1.6g/kg protein; group three received 3.2g/kg protein. All three groups started off on a weight maintenance diet for the first 10 days to allow their bodies to adjust to the amounts of protein they were receiving. Then, the amount of calories per day was reduced by 40% for all three groups (enough to lose about two pounds per week) for the remaining 3 weeks of the study. All food was provided by the researchers and exercise was controlled and monitored in all three groups.
At the conclusion of the study, researchers determined that the participants in all three groups lost 3-3.4 kg, or 6.6-7.5 pounds. The proportion of muscle loss versus fat loss was greater in the group that consumed merely the RDA for protein, and muscle loss was significantly less in the groups that contained two and three times the RDA for protein. However, there was no significant difference between the two intervention groups. Thus, while it may be beneficial to consume twice the RDA for protein in order to stem muscle loss during weight loss, there does not appear to be an increased beneficial effect in consuming more than twice the RDA.
Good sources of protein include meats, fish, poultry, eggs, nuts, beans, legumes, and soy products. Dairy and whole grains provide a good amount as well.
To determine your daily protein needs, divide your weight in pounds by 2.2 to convert it to kilograms. Then multiply that number by 1.6 to determine the number of grams of protein you would need to eat per day to consume twice the RDA. For example a 125-pound woman weighs 56.8 kg; 56.8kg x 1.6 g = 91g of protein per day.
That sounds like a lot of protein, but it is not a difficult goal to meet. A typical day might look like this:
A poached egg with 2 pieces of whole grain toast and a piece of fruit for breakfast; a high protein bar for a mid-morning snack; a turkey sandwich, green salad, and a Greek yogurt for lunch; a handful of almonds and a glass of milk (or soymilk) as an afternoon snack; beef or tofu and veggie stir fry with brown rice for dinner.
If you have difficulty meeting your protein goals, you may consider supplementing your diet by adding a few ounces of silken tofu or protein powder to a yogurt and fruit smoothie. Perhaps even trying milk protein isolate may make a great difference. And keep in mind that it all accumulates throughout the day; if you make a conscious effort to eat at least a little protein with every meal or snack, you’ll be surprised how quickly it will add up.