A randomized crossover, pilot study examining the effects of a normal protein vs. high protein breakfast on food cravings and reward signals in overweight/obese “breakfast skipping”, late-adolescent girls

BACKGROUND: This pilot study examined whether the addition of a normal protein (NP) vs. high protein (HP) breakfast leads to alterations in food cravings and plasma homovanillic acid (HVA), which is an index of central dopamine production, in overweight/obese ‘breakfast skipping’ late-adolescent young women. METHODS: A randomized crossover design was incorporated in which 20 girls (age 19 ± 1 y; BMI 28.6 ± 0.7 kg/m(2)) consumed 350 kcal NP (13 g protein) breakfast meals, 350 kcal HP (35 g protein) breakfast meals, or continued breakfast skipping (BS) for 6 consecutive days/pattern. On day 7 of each pattern, a 4 h testing day was completed including the consumption of breakfast (or no breakfast) followed by food craving questionnaires and blood sampling for HVA concentrations throughout the morning. RESULTS: Both breakfast meals reduced post-meal cravings for sweet and savory foods and increased HVA concentrations vs. BS (all, p < 0.05). Between breakfast meals, the HP breakfast tended to elicit greater reductions in post-meal savory cravings vs. NP (p = 0.08) and tended to elicit sustained increases in HVA concentrations prior to lunch vs. NP (p = 0.09). Lastly, HVA concentrations were positively correlated with the protein content at breakfast (r: 0.340; p < 0.03). CONCLUSIONS: Collectively, these findings suggest that the addition of breakfast reduces post-meal food cravings and increases homovanillic acid concentrations in overweight/obese young people with higher protein versions eliciting greater responses.