Mild hunger pangs are harmless, natural reminders to "fill up the bread basket." By contrast, ravenous hunger from starvation is obviously harmful to health because of the associated malnourishment. Short-term hunger is often uncomfortable and may lead to low blood sugar, but no evidence exists that it’s physically harmful.
Hunger is a natural physiological process, similar to thirst, that gets your attention and motivates you to seek food. Mild hunger is completely normal and is an effective signal to stop you from working, playing or chatting on the phone so that you can eat something to fuel your brain and body. Hunger is controlled in the hypothalamus -- a relay station in your brain. Incoming hormonal messages from your stomach, intestines and liver tell the lateral part of the hypothalamus that your blood sugar is too low and that it’s time to eat. Interestingly, if this part of the brain is destroyed, even a starving person would have no desire to eat. In contrast, the medial part of your hypothalamus is the satiety center, which signals you to stop eating. When this part is damaged due to cancer or head injury, a person will eat uncontrollably and rapidly gain weight.
No one ever said that hunger is enjoyable, which makes sense because it’s meant to be a bit of a “wake-up call” to the conscious part of your brain to gain your full attention. In essence, it’s a powerful survival mechanism inherited through evolution. The most common initial feeling associated with hunger is a rumbling stomach and intestinal pains. Not everyone experiences these, and it’s a bit of a mystery as to why they occur, but it’s often explained as autonomic muscle contractions in the stomach and intestines due to the anticipation of food. Hunger is also associated with low blood sugar levels, which affect the brain because glucose is its only fuel. Symptoms of low blood glucose include fatigue, weakness, irritability, moodiness and reduced ability to concentrate.
Potential Health Issues
Any health issues associated with hunger are directly related to the amount of time you go without food as well as your health status. As long as you’re at a healthy weight and have a strong heart, experiencing hunger pains due to a restricted-calorie but otherwise nutritious diet is not risky or harmful. Some people fast for a few days or a week for the health benefit without suffering any ill effects as long as they stay well-hydrated. About the only group that should be cautious of hunger pains are diabetics because of the association with low blood sugar. For diabetics who take insulin injections, the sensation of hunger following meals may indicate that they injected a little too much medicine.
Many Americans don’t eat because of physical hunger; they eat due to habit, addiction and/or psychological attachment. If a situation arises that deprives people of food for longer than they are used to, the resulting hunger pains may be more in their heads than their bellies. However, it’s no laughing matter because withdrawal symptoms from certain compounds in food can include intense cravings, anxiety, depression and insomnia, which can negatively impact your health.
- Human Metabolism: Functional Diversity and Integration; J. Ramsey Bronk
- Human Physiology: An Integrated Approach; Dee Silverthorn and William Ober
- Public Health Nutrition: From Principles to Practice; Mark Lawrence and Tony Worsley
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.