Food cravings have been experienced by most everyone and are fairly common. There are cases, however, in which intense food cravings are unwanted and become intrusive.

Giving in to cravings from time to time is no big deal, but when these become uncontrollable, it can lead to overeating and excess weight-gain (Myers Et al., 2018). Overeating and weight-gain overtime can elevate a person’s risk for obesity, diabetes, and vascular problems.

So how does one control food cravings to prevent going down this slippery slope? 

Where do Cravings Come From? 

According to a blog post by the Harvard’s School of Public Health, cravings come from a unique interplay between the brain, hormones, behaviors, and environment. They mention that since the brain’s reward system is wired to respond more strongly to hyperpalatable (junk) food.

Junk food tends to be high in fat, salt, and/or sugar which make it very palatable- hyperpalatable. This leads to a stronger response by the reward system in the brain and how the brain processes hormones involved in hunger and metabolism; which contribute to more cravings (“Cravings,” 2021).

At the same time, easy access to junk food as well as unhealthy habits such as eating junk food while watching television or when bored can contribute to such cravings. 

Hormones and Cravings 

A common denominator in many food craving episodes are sleep, hunger, stress and metabolic hormones.  Hormones are a very important part of the metabolic process, hunger, and cravings.

Hormones are messages sent from one part of the body to the other giving instructions for something to happen. When these aren’t working properly or their message isn’t processed correctly it can lead to a range of complications. The following are a few examples: 

Leptin. Leptin is a hormone made by fat cells (or adipose) in proportion to fat levels and has an inhibiting effect on appetite. When not enough leptin is produced, appetite can go haywire. Laboratory mice with leptin deficiency become extremely obese, for example.

Ghrelin. Ghrelin is a hormone that stimulates hunger, too much of it can lead to excess food intake, too little of it and a person lacks an appetite. 

Insulin. Insulin leads to intake of sugar from the blood into cells of the body. Too much of it and a person can get low blood sugar and subsequent craving of sweets to bring levels back up.

Many diets focus on eating food with a low-glycemic index, meaning it leads to lower insulin spikes, because it is thought to prevent excessive insulin and hunger oscillations (“Keep your weight down,” 2014). 

Cortisol. Cortisol is a stress hormone which can suppress hormone in the short-run, but stimulate it in the long-run. Excessive stress and cortisol can contribute to a person’s excessive food intake. 

Gastrin. Gastrin is released by G-cells of the stomach lining in response to sensory stimulus from food and/or thoughts of foods.

This triggers the cephalic phase of digestion, in which sensory stimulation (by sight, smell, or taste) or idea of food leads to an increase in gastric acid concentration (HCl) and stomach motility. It pushes a craving to physical symptoms of hunger which may be tougher to control.

Preventing Cravings

Preventing food cravings depends a lot on what is contributing to the craving in the first place, but a couple of approaches can help. 

Get good sleep. Inadequate sleep can disrupt the hunger hormones leptin and ghrelin- leading to too much ghrelin (associated with hunger) and too little leptin (associated with satiety) (Taheri Et al., 2004).

Furthermore, disruptions to the sleep-and-wake cycle can disrupt the circadian rhythm, which may also contribute to abnormal eating patterns like late-night eating.

Exercise. Exercise is a great way to manage stress and help get rid of stress-related cravings and over-eating. A review by Myers Et al. (2018) mentions a study that found that walking 5 minutes out of every hour reduced cravings compared to continuous sitting.

Exercise may reduce appetite by shunting blood away from the gut and into the limbs in order to prepare the body for movement via the sympathetic nerve response.

Practice a Balanced Diet. Eating a balanced diet rich in fruits and vegetables may help keep a person feeling full for longer. Fruits and vegetables have lots of fiber which helps control blood sugar and thus insulin spikes and related sugar cravings.

Fiber has also been found to help with satiety by helping a person feel fuller for longer. Preventing long periods of no-eating (hunger) may also prevent excessive craving and binge eating later in the day. 

References-

1. Myers CA, Martin CK, Apolzan JW. Food cravings and body weight: a conditioning response. Curr Opin Endocrinol Diabetes Obes. 2018 Oct;25(5):298-302. doi: 10.1097/MED.0000000000000434. PMID: 30048258; PMCID: PMC6411047.
2. Cravings. (2021, April 27). Retrieved from https://www.hsph.harvard.edu/nutritionsource/cravings/
3. Keep your weight down and your energy up with the glycemic index. Harvard Health. (2014, November 13). Retrieved November 5, 2021, from https://www.health.harvard.edu/staying-healthy/keep-your-weight-down-and-your-energy-up-with-the-glycemic-index.
4. 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 medicine, 1(3), e62. https://doi.org/10.1371/journal.pmed.0010062