The Whys and Wherefores of Food Cravings

November 15th, 2017 | Posted in Info | Uncategorized

There are probably not many people out there who have never experienced a food craving. The term food craving refers to an intense desire to consume a specific food. In the past the desire to eat was largely governed by metabolic needs. However, today we live in a world where highly palatable food is available all day every day without the need to expend any energy to get it.

This is all well and good if you are craving a green salad, go ahead and eat it! However, often cravings are for sugary or fatty foods such as chocolate, cakes, crisps, potatoes and refined carbohydrates.

Here’s a look at some of the factors underlying food cravings:

Cravings, Dieting and Weight Loss

The relationship between food cravings and dieting is mixed. Multiple studies have concluded that calorie restriction for at least 12 weeks is associated with reduced food cravings (1), while others have shown that calorie restriction may increase food cravings. Frequent food cravings can slow down weight loss in those trying to lose weight (2).

Hormonal Factors

In menstruating women the monthly hormonal fluctuations can lead to increased food cravings with higher oestrogen levels leading to more sweet and carbohydrate cravings (3,4). Ghrelin is a hormone produced in the digestive tract that increases hunger. People with higher ghrelin have significantly more food cravings. Higher cortisol, insulin, and chronic stress are all predictive of future weight gain (5).

Junk the Junk

Research has found that in people who are susceptible to obesity cravings are increased by junk food consumption and even persist for several weeks after eating junk food (6). Some individuals may even have an addictive-like response to highly processed foods containing fats and/or refined carbohydrates (7).

Take Control

Feeling in control of eating is associated with greater weight loss. This suggests it is the behaviour that follows food cravings rather than simply their frequency that contributes to successful weight management (8).

Exercise

Some research suggests that exercisers have more frequent cravings and greater difficulty in resisting eating compared to non exercisers. This may be attributable to greater energy demands. However, in the long term exercise may reduce food cravings and increase the ability to resist cravings, particularly in men (9).

One study found that office workers who engaged in a 5 minute microbout of moderate intensity exercise 6 times over the course of the day had improved energy and mood and reduced food cravings (10).

Blood sugar imbalances

Your body needs to maintain stable blood sugar levels in order for you to function physically and mentally. If you eat sugary foods, refined carbohydrates and processed foods or drink caffeinated drinks or alcohol you may be on a blood sugar roller coaster with the lows accompanied by a desire for another pick me up.

Food intolerances

We often crave the foods to which we are intolerant. This is thought to be due to the release of endorphins (feel good chemicals) when the culprit foods are eaten. We then become addicted to the endorphins and crave the foods that cause their release.

Nutritional deficiencies

If your body is malnourished it may crave the foods it needs.

Irregular eating patterns

The body likes routine. Not eating breakfast or getting overly hungry can lead to cravings later in the day and possibly uncontrolled eating in the evening. 

Dehydration

Thirst is often mistaken for hunger and particularly for the need for sugar.

Boredom or stress

Food may be used to distract us from both boredom and stress.

 

References

  1. 1. Obes Rev. 2017 Oct;18(10):1122-1135. Extended calorie restriction suppresses overall and specific food cravings: a systematic review and a meta-analysis. Kahathuduwa CN, Binks M, et al.
  2. 2. J Behav Med. 2017 Aug;40(4):565-573. Impact of food craving and calorie intake on body mass index (BMI) changes during an 18-month behavioral weight loss trial. Buscemi J, Rybak TM et al.
  3. 3. Curr Obes Rep. 2017 Jul 31. Weight Loss and Appetite Control in Women. Hintze LJ, Mahmoodianfard S et al.
  4. 4. Physiol Behav. 2016 Oct 15;165:304-12. Estradiol, SHBG and leptin interplay with food craving and intake across the menstrual cycle. Krishnan S, Tryon RR, Horn WF et al.
  5. 5. Obesity (Silver Spring). 2017 Apr;25(4):713-720. Stress, cortisol, and other appetite-related hormones: Prospective prediction of 6-month changes in food cravings and weight. Chao AM, Jastreboff AM et al.
  6. 6. Neuropsychopharmacology. 2016 Dec;41(13):2977-2986. Eating ‘Junk-Food’ Produces Rapid and Long-Lasting Increases in NAc CP-AMPA Receptors: Implications for Enhanced Cue-Induced Motivation and Food Addiction. Oginsky MR, Goforth PB et al.
  7. 7. Appetite. 2017 Aug 1;115:45-53. Wanting and liking: Separable components in problematic eating behavior? Polk SE, Schulte EM et al.
  8. 8. Eur J Clin Nutr. 2017 May;71(5):625-630. It is not how much you crave but what you do with it that counts: behavioural responses to food craving during weight management. Smithson EF, Hill AJ.
  9. 9. Appetite. 2017 Nov 1;118:82-89. Cross-sectional and longitudinal associations between different exercise types and food cravings in free-living healthy young adults. Drenowatz C, Evensen L et al.
  10. 10. Int J Behav Nutr Phys Act. 2016 Nov 3;13(1):113. Effect of frequent interruptions of prolonged sitting on self-perceived levels of energy, mood, food cravings and cognitive function. Bergouignan A, Legget KT et al.