Are Six Meals Better Than Two? Recent Study Shows Lean Mass Gains on Std. Energy-Reduced Diet W/Out Differences in Fat Loss W/ 6 vs. 2 Meals/Day - Do You Have to React?

Do the results of the latest randomized controlled cross-over study from the California State University mean that you have to change your eating habits? Find out in today's SuppVersity Article!

If you are a SuppVersity reader you know that the scientific evidence that eating four meals instead of two when dieting is scarce. More recently, there have actually been more studies to suggest that eating very frequently like 6+ meals per day may eventually ruin your dieting efforts because (a) the constant grazing won't allow your insulin levels to drop and (b) people tend to eat "a little too much" with each of these meals, so that - eventually - they are missing their target energy intakes. Now, an ahead of print article in the peer-reviewed scientific journal Nutrition Research suggests that, in a tightly controlled scenario and with significantly overweight, not to say obese women as subjects, an increase in food frequency from two to six meals per day can have beneficial effects on their weight loss success.
More specifically, Michelle Kulovitz Alencar et al. (Alencar. 2015) set out to deterimine whether
either a two meal (2MF) or six meal frequency (6MF) regimen can improve body composition and blood-based markers of health while consuming a portion-controlled equihypocaloric diet.

Figure 1: Overview of the study design (Alencar. 2015) | Explanation of the indices: (a) resting metabolic rate, (b) blood pressure (c) visual analogue scale, (d) area under the curve

The study was a randomized-controlled cross-over trial. Thus, the researchers who randomly assigned their N = 11 obese women (52 ± 7 years, 101.7 ± 22.6 kg, 39.1 ± 7.6 kg/m²) who had been to either of the treatment conditions (2MF or 6MF) for two weeks, ensured that by having a washout after the initial two weeks and another two-week intervention phase thereafter, none of the meal frequency patterns had an "unfair" advantage of being "the first" while. Here is an overview of the key facts directly from the research paper:

• SuppVersity Classic: Grazin' Study Shows: Increased Eating Frequency Bad For Obese and Lean Men. Reduced Diet-Induced Thermogenesis and Blunted Lipolysis Could Promote Future Weight Gain | read more.

  The 2MF pattern participants were instructed to consume allocated meals every 5-6 hours while awake. 
• The 6MF pattern participants were instructed to consume allocated meals/snacks every 2-3 hours while awake. 
• Meals provided to participants were defined as an eating occasion with a caloric intake between 200 and 300 kcals, while a snack was defined as an eating occasion with a caloric intake between 100 and 200 kcals. 
• Throughout all treatment conditions, food products were identical and participants received the identical assortment of pre-packaged food products containing 1,200kcal/day with ~75g/day of protein and a macronutrient ratio of 52% carbohydrates, 27% protein, and 21% fat. 
• Participants consumed their designated meal pattern eating only Nutrisystem® meal products which were supplied to the participant. Participants also supplemented this diet with a limited selection and quantity of Nutrisystem®-approved fresh fruits and vegetables. The additional fresh items added accounted for only approximately 187 kcals/day, or 15% of daily caloric intake of the participants’ daily total of ~1200 kcals per day. 
• The participants consumed identical food products throughout the study.

Participants followed their respective MF pattern for the two weeks of Phase I. They the
At the same time a cross-over design like this "virtually" doubles the number of subjects. The same obviously goes for the data Alencar et al. could use to compare the effects of the two meal frequency patterns on body composition, glucose, insulin and lipid components by their individiual responses to a test meal.
Speaking of the effects. As you may have guessed from my preliminary remarks in the introduction, both groups successfully lost (p≤0.05) body mass (=total weight | 2MF: -2.8 ± 1.5 vs. 6MF: -1.9 ± 1.5 kg) - in fact with a slight but highly non-significant "advantage" for the two-meal pattern.

Figure 2: Changes in body composition and resting metabolic rate in both groups (Alancar. 2015).

Since differences in the effects of dieting on glucose, insulin, total-cholesterol, or LDL-C (p>0.05) between the two groups were not observed, one could falsely conclude that the two-meal strategy was in fact minimally more effective.
References:

• Alencar, Michelle K., et al. "Increased meal frequency attenuates fat-free mass losses and some markers of health status with a portion-controlled weight loss diet." Nutrition Research (2015).
• Böhm, A., and B. L. Heitmann. "The use of bioelectrical impedance analysis for body composition in epidemiological studies." European journal of clinical nutrition 67 (2013): S79-S85.
• Fogteloo AJ, Pijl H, Roelfsema F, Frölich M, Meinders AE. Impact of meal timing and frequency on the twenty-four-hour leptin rhythm. Horm Res. 2004;62(2):71-8.
• Koopman, Karin E., et al. "Hypercaloric diets with increased meal frequency, but not meal size, increase intrahepatic triglycerides: A randomized controlled trial." Hepatology 60.2 (2014): 545-553.
• Romero-Corral, Abel, et al. "Accuracy of body mass index in diagnosing obesity in the adult general population." International journal of obesity 32.6 (2008): 959-966.