Understanding the impact of hormones on weight loss


Hormones play a major role in how we experience weight change. Not only do they affect our body’s response to food, they also make us feel better or worse when we change our dieting habits. Why, for example, do we crave sugar when we diet?

Understanding the science of hormones when dieting can help you take positive control of your battle against food, and make yourself feel much better.

The science

There are seven key gut hormones that affect appetite: Peptide YY, GLP-1, Cholecystokinin, Pancreatic polypeptide, Oxyntomodulin, Ghrelin and Leptin. The principal two are Ghrelin, which stimulates appetite, and Leptin, which suppresses appetite. Ghrelin is typically high before we eat and low after we eat, whereas for Leptin it is the reverse. Consequently, if we want to lose weight we want to promote more Leptin and less Ghrelin. Once these hormones are released, they are transported to the hypothalamus in the brain – our body’s regulatory system – and a response is coordinated.

Adopting a diet that incorporates periods of fasting, like the 5:2, will both promote the release of Ghrelin (making you crave foods with fast energy release, like sugar and high-fat meals) and will also reduce Leptin levels in your system. Fasting simultaneously reduces your metabolic rate, decreasing your capacity to break down these poor-quality foods, so they are stored as fat instead. There are a variety of strategies that you can implement in your lifestyle that can balance out these hormones, helping you to feel fuller for longer, have more energy throughout the day and ultimately, prevent any additional weight gain.

How to balance your hormones

+ Eat high protein meals – this will lower your Ghrelin (appetite stimulator) levels. The body works harder to break down protein than sugar and fat, therefore you will feel fuller for longer.

+ Avoid simple sugars and saturated fats – these can decrease your Leptin (appetite suppressor) levels.

+ Eat omega-3 (good fats) rich foods – these foods can help increase Leptin levels and further reduce the level of insulin resistance.

+ Eat regularly and consistently – this can help both increase Leptin levels and decrease Ghrelin levels.

+ Avoid foods high in fructose – this can reduce circulating Leptin and Insulin levels.

+ Sleep more – Lack of sleep can lead to more Ghrelin and less Leptin.

You can read more about the subject of hormones and dieting via the below articles and web link:

Teff, K. L., Elliott, S. S., Tschöp, M., Kieffer, T. J., Rader, D., Heiman, M., … & Havel, P. J. (2004). Dietary fructose reduces circulating insulin and leptin, attenuates postprandial suppression of ghrelin, and increases triglycerides in women. The Journal of Clinical Endocrinology & Metabolism89(6), 2963-2972.

Cummings, D. E., Weigle, D. S., Frayo, R. S., Breen, P. A., Ma, M. K., Dellinger, E. P., & Purnell, J. Q. (2002). Plasma ghrelin levels after diet-induced weight loss or gastric bypass surgery. New England Journal of Medicine346(21), 1623-1630.

Taheri, S., Lin, L., Austin, D., Young, T., & Mignot, E. (2004). Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index. PLoS Med1(3), e62.

Weigle, D. S., Breen, P. A., Matthys, C. C., Callahan, H. S., Meeuws, K. E., Burden, V. R., & Purnell, J. Q. (2005). A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations. The American journal of clinical nutrition82(1), 41-48.

Blom, W. A., Lluch, A., Stafleu, A., Vinoy, S., Holst, J. J., Schaafsma, G., & Hendriks, H. F. (2006). Effect of a high-protein breakfast on the postprandial ghrelin response. The American journal of clinical nutrition83(2), 211-220.