Protein and Dairy: A Dieters Best Friends?

New research has found that increased consumption of protein, particularly protein from dairy foods, helps people who are dieting lose more fat and preserve lean body mass (muscle) during exercise- and diet-induced weight loss. The new study, which was published in the September issue of the Journal of Nutrition, studied three groups of women, all of whom were overweight or obese premenopausal females. The aim of the study was to find out how daily exercise and a reduced-calorie diet varying in protein amount and dairy would affect the type of weight lost (fat mass loss versus lean body mass loss). The women were randomized to a high-protein/high-dairy diet, an adequate-protein/medium-dairy diet or an adequate-protein/low-dairy diet. The women also exercised seven days per week.

Researchers found that although all three groups lost identical amounts of weight, the higher-protein/higher-dairy group lost significantly more total body fat and abdominal fat and gained more lean body mass and muscle strength. In fact, the weight lost in the higher-protein/higher-dairy group was 100% fat. At the same time, that group gained muscle, which favorably changed their overall body compositions. Since muscle burns more calories at rest than fat does, this kind of change in body composition will only further assist people with their weight loss goals. The lower-protein/low-dairy group actually lost muscle mass. The higher-protein/high-dairy group also lost twice as much abdominal fat than the group whose diet was lower in protein and low in dairy foods.

Other emerging research on protein is finding that it's more important to balance protein intake throughout the day rather than consuming a large amount of protein all at one time, which is typical of the American diet because we eat small amounts of protein at breakfast and lunch but have an oversized portion of protein at dinner. The common meal pattern in the U.S. provides about 10 grams of protein for breakfast, 20 grams of protein for lunch, and 60 grams of protein for dinner--but this is unbalanced. Rather than recommending a specific amount of protein per kilogram of body weight, scientists are leaning more toward recommending a specific minimum amount of protein per meal. Getting about 30 grams of protein per meal seems to result in greater increases in muscle tissue gain, and muscle revs metabolism.

The amount of protein that one should consume at each meal is approximately 30 grams of high-quality protein (protein that contains all 9 essential amino acids--generally protein from animal sources such as meat, eggs, and dairy, and the complete vegetable protein soy). This equates to about 1.5 grams of protein per kilogram of body weight. Of particular interest is that research is showing that the 30 grams of protein recommended per meal also needs to be high in the particular amino acid leucine. About 2.5 to 3.0 grams of leucine is recommended per meal. Most proteins contain about 8% leucine.

While protein has many benefits for those trying to lose weight or maintain a healthy weight, getting too much protein can be detrimental to your health. The recommended upper limit for protein intake is 35% of your total daily calories.

Kari Hartel, RD, LD is a Registered Dietitian and freelance writer based out of St. Louis, MO. Kari is passionate about nutrition education and the prevention of chronic disease through a healthy diet and active lifestyle. Kari holds a Bachelor of Science in Dietetics from Southeast Missouri State University and is committed to helping people lead healthy lives. She completed a yearlong dietetic internship at OSF St. Francis Medical Center in Peoria, IL, where she worked with a multitude of clients and patients with complicated diagnoses. She planned, marketed, and implemented nutrition education programs and cooking demonstrations for the general public as well as for special populations, including patients with cancer, heart disease, diabetes, Alzheimer's disease, obesity, and school-aged children. Contact Kari at [email protected].

1. Prev:Measuring Fat and Weight Loss: More Than Stepping on the Scale
2. Next:Kañiwa: The Next Superfood?