Key points
- Mood is improved similarly in self-reported ‘carb cravers’ and non-cravers after meals high in protein, fat, or carbohydrate, suggesting energy balance is the key factor influencing cravings.
- High protein diets are linked to reduced sugar cravings but comparisons of small differences in protein intake show no significant effect.
- Protein, overall increases satiety and reduces cravings for any macro or taste.
It is commonly stated by practitioners that protein enhances satiety (the satisfaction from meals) and reduces food intake (along with benefits to bone, systemic, and muscular health) and that it also reduces cravings for sugar. While the evidence convincingly demonstrates that increased protein intakes do increase thermogenesis and satiety compared to diets of lower protein content and that high-protein intakes reduce subsequent energy intake,1 the evidence for an effect of protein on sugar cravings is less clear.
Mood is improved similarly in both ‘carbohydrate cravers’ and non-cravers after meals high in fat, carbohydrate, or protein,2 suggesting that the intake of any form of energy practically eliminates cravings in the short-term, irrespective of whether you self-report as a sugar-craver or not. This is also suggested by research which shows that you crave what you restrict.3
In other words, if you restrict protein or fat, you typically crave those, and if you restrict carbohydrate, you typically crave that. However, these restriction enhanced cravings have no effect on subsequent food intake, so irrespective of what people crave due to avoiding it, they typically don’t actually choose to eat foods high in the macronutrient they crave!3
Mood is improved similarly in both ‘carbohydrate cravers’ and non-cravers after meals high in fat, carbohydrate, or protein
This finding is supported by our knowledge of human nutrition related to anthropology. In a survival setting, we would be inclined to eat what we had available to supply necessary amino acids, even if those foods were not especially high in protein. In other words, having a little is better than going without. Protein leverage theory is based on this idea, namely that we will continue to eat (what is readily available) until we have achieved amino acid sufficiency.4 There are also considerable variations between what individuals themselves will crave and this is likely to be heavily influenced by behavioural ‘types’5 and psychosocial factors.
In contrast to the findings above, those following a low-carbohydrate, higher-protein, high-fibre diet had reduced sugar and sweet cravings.6 And this is a common finding clinically. However in a comparison of a lower protein (21%) diet vs higher- (29%) in people with type 2 diabetes, no differences in cravings were observed between the groups,7 notwithstanding that this is a very modest difference in protein intakes (i.e. would it have been the same if the protein intake was actually high?)
Finally, in one of the few studies directly looking at the effects of a high protein (vs low-protein) meal, a higher protein breakfast led to greater feelings of fullness and reduced cravings for both savoury and sweet.8
a higher protein breakfast led to greater feelings of fullness and reduced cravings for both savoury and sweet
Conclusions
Protein does increase satiety and has the largest effect on satiety of any of the macronutrients. This could provide pronounced benefits to the ‘autoregulation’ of energy intake and thus, reduce the propensity to overeat. This satiety effect is likely to have some effect on cravings for food overall (irrespective of savoury or sweet). But the reasons we ‘crave’ any particular food, foods, or tastes is more complex than simply the physiological requirements for macronutrients or the metabolic status of an individual and psychosocial, behavioural, and emotional factors all deserve consideration.
References
1. Halton TL, Hu FB. The Effects of High Protein Diets on Thermogenesis, Satiety and Weight Loss: A Critical Review. Journal of the American College of Nutrition. 2004;23(5):373-85.
2. Toornvliet AC, Pijl H, Tuinenburg JC, Wever BME-d, Pieters MSM, Frölich M, et al. Psychological and metabolic responses of carbohydrate craving obese patients to carbohydrate, fat and protein-rich meals. International Journal of Obesity. 1997;21(10):860-4.
3. Coelho JS, Polivy J, Herman CP. Selective carbohydrate or protein restriction: Effects on subsequent food intake and cravings. Appetite. 2006;47(3):352-60.
4. Simpson SJ, Raubenheimer D. Obesity: the protein leverage hypothesis. Obes Rev. 2005;6(2):133-42.
5. Harvey C, Schofield G, Williden M. The lived experience of healthy adults following a ketogenic diet: A qualitative study. J Holist Perf. 2018;7782018(1):3638.
6. Ohlsson B, Darwiche G, Roth B, Bengtsson M, Höglund P. High fiber fat and protein contents lead to increased satiety reduced sweet cravings and decreased gastrointestinal symptoms independently of anthropometric hormonal and metabolic factors. Journal of Diabetes & Metabolism; 3. 2017;8.
7. Watson NA, Dyer KA, Buckley JD, Brinkworth GD, Coates AM, Parfitt G, et al. Reductions in food cravings are similar with low-fat weight loss diets differing in protein and carbohydrate in overweight and obese adults with type 2 diabetes: A randomized clinical trial. Nutrition Research. 2018;57:56-66.
8. Ortinau LC, Hoertel HA, Douglas SM, Leidy HJ. The impact of a protein-rich breakfast on food cravings and reward in overweight/obese ‘breakfast skipping’ adolescent girls. The FASEB Journal. 2013;27(1_supplement):1075.9-.9.
