Can High Protein Intakes Reduce Abdominal Fat?
Tom McCullough MEd.

Arciero PJ, Ormsbee MJ, Gentile CL, Nindl BC, Brestoff JR, Ruby M. Increased protein intake and meal frequency reduces abdominal fat during energy balance and energy deficit. Obesity (Silver Spring). 2013 Jan 2. [Epub ahead of print]


Unrefined, complex carbohydrates and lean protein diets are used to combat obesity, although it's unknown whether more frequent meals may improve this response. The effects of consuming traditional (∼15%) versus higher (∼35%) protein intakes as three or six meals/day on abdominal fat, postprandial thermogenesis (TEM), and cardiometabolic biomarkers in overweight individuals during 28 days of energy balance (BAL) and deficit (NEG), respectively were compared.

Overweight individuals (n = 30) were randomized into three groups: two high-protein groups (35% of energy) consumed as three (HP3) or six (HP6) meals/day and one group consumed three meals/day of a traditional intake (TD3). Following a 5-day baseline control (CON), subjects consumed their respective diets throughout a 56-day intervention consisting of two, 28 day phases: a BAL followed by a NEG phase (75% of energy needs). Total body fat (BF) and abdominal BF (ABF), body weight (BW), TEM, and fasting biomarkers were assessed at the end of CON, BAL, and NEG phases.

BW remained stable throughout CON and BAL in all groups, whereas BF (P < 0.001) and ABF (P < 0.01) decreased in HP groups and lean body mass (LBM) and leptin increased in HP6. Following NEG, BW decreased in all groups. BF, ABF, and leptin decreased in HP groups; LBM remained higher (P < 0.05), and TEM was highest in HP6 (P < 0.05).

Consuming increased protein (∼35%) more frequently (6×) throughout the day decreases BF and ABF, increases LBM and TEM, and favorably affects adipokines more than current recommendations for macronutrients consumed over three meals/day in overweight individuals during both BAL and NEG.




As you can see from the graph above, a diet high in protein boosts energy expenditure, and this effect is boosted by eating six rather than three meals a day.

In this study researchers examined 30 inactive overweight people, average age of 45, that lasted for 2 periods of 28 days which was a total of 56 days.

During period 1 the subjects ate exactly the same number of calories every day as they burned [BAL]; during period 2 they were only given 75% of the number of calories they burned daily [NEG].

The 1st group was called the TD3 group which ate three meals consisting of 15% of the calories coming from protein, 60% from carbohydrates and 15% from fat.

The 2nd group was called the HP3 group which ate three meals a day consisting of 35% protein, 45% carbohydrates and 20% fat. 

The 3rd group (HP6) ate six meals a day which was the same consistency of the HP3 group.

At the end of the 2 periods (56 day) of the testing the HP3 and HP6 groups lost significantly more gat then the TD3 group. Further, the HP6 group lost body fat t a significantly faster rate that did the HP3 and TD3 groups. The HP6 group also gained a significant about of lean body mass while the other two lost small amounts.

Researcher wrote: "Extrapolating to all meals eaten during the BAL and NEG period (56 days total) would result in an expenditure of 3444.0, 3259.2, and 6333.6 total kcals for TD3, HP3, and HP6, respectively, and clearly highlights the profound impact of increased dietary protein and meal frequency on thermogenesis and body composition."

The fact that only the HP6 group actually gained lean tissue means that when in a negative caloric balance is very important to a bodybuilder. This to me means that when dealing with subjects (bodybuilders) that are doing weight training in combination with a diet (NEG) it is very possible to gain muscle mass while losing body fat. Especially when using anabolic steroids and hGH. So keep the protein high and spread the meals out to a minimum of 6 meals a day. Kind of blows these fasting diets out of the water IMHO. Protein stimulates thermogenesis and that has been known for years, the combination of extra protein and keeping a steady supply in the diet through frequent meals must also stimulate protein synthesis, even in those who don’t exercise.