Food is essential for sustaining life as it provides the fuel, building blocks and substances needed for various biochemical processes. Without food, death is a certainty although the human body can survive for 2 to 3 weeks without food. However, most of us would not be able to function at our best without eating every few hours. Just as too little food can be harmful and even deadly, similarly excessive eating is associated with various dangers.
What is excessive eating?
Excessive eating can refer to two phenomena – overeating and excessive hunger. While overeating is a voluntary action, hunger is a sensation that the body generates to signal us that food is needed. We can stimulate hunger (primarily by not eating) and satisfy it (by eating) but ultimately this sensation is not under our full control.
Excessive hunger or increased appetite is medically referred to as polyphagia. It may be difficult to identify whether excessive eating in children is due to excessive hunger or whether it is linked to overeating without hunger sensations. However, most adults will be able to make the differentiation.
While excessive hunger can lead to overeating, many people also overeat even without feeling hungry. Overeating and excessive hunger may at times be caused by the same factors. Collectively we refer to it as excessive eating but it is important to understand the distinction between these conditions.
It is also important to note that sometimes we do feeling like we overate (stuffed or bloated feeling) despite having a small portion of food. This sensation of fullness may be linked to a number of different digestive conditions and is not due to actual overeating.
Read more on overeating.
How much should we eat daily?
Hunger is influenced by our eating habits, the quantity of food and calories within our daily meals. However, relying on hunger alone as a signal for how much we should eat can sometimes be misleading, especially when there are underlying medical conditions like diabetes.
Even emotional states and the use of substances like alcohol and certain drugs may disturb the hunger sensation thereby leading to increased hunger despite the body not requiring food. Ultimately this can contribute to weight gain among other consequences.
Food intake should be dependent on the calorie needs of the body within a day. Understandably people who are more active will require more food, not necessarily in quantity but rather in calories. Conversely, people who are less active or sedentary will require less calories.
The average adult male requires approximately 2,500 calories daily while women require 2,000 calories daily. However, there is a large degree of variation among individuals depending on their activity levels, age, height, muscle mass and so on.
Sufficient food intake is a major component in a constant health body weight, suitable energy levels as well as physical, mental and emotional wellbeing. These factors, particularly body weight, can be used as metrics to determine whether the daily food intake is sufficient.
Calories alone are not the only consideration when determining how much a person needs to eat daily. The body also requires vitamins, minerals, electrolytes and water. Therefore a balanced diet is necessary to ensure sufficient intake of all macro- and micronutrients, beyond just the daily calorie needs.
Read more on calorie count.
Causes of Excessive Eating
The following causes of excessive eating may include conditions where constant hunger is present or absent. Therefore these causes encompass both overeating and constant hunger. In the majority of cases this will lead to weight gain over time but when excessive eating is accompanied by unintentional weight loss then further medical investigations are necessary.
Changes in the body may occur which can lead to excessive eating. These changes are not due to any disease or disorder. This includes:
- Increased physical activity as the body requires a larger energy supply. It is more likely to be seen with sustained physical activity as some people experience a loss of appetite with a single episode of physical strain.
- Pregnancy where the nutrient demands are greater to sustain both mother and child. Pregnancy hormones may also disrupt the appetite centers.
- Sedentary lifestyle where excessive eating may be a result of boredom. Many people experience this for a short period during vacations.
- Food availability particularly where there are new foods or foods that a person finds tasty may stimulate the appetite but it is also usually a short term effect.
Various diseases and disorders may result in excessive eating. Some of these conditions may affect the hunger centers and appetite control. However, at other times it can arise from problems in the stomach and other digestive organs causing sensations which a person incorrectly perceives as hunger. Similarly food intake may alleviate some of these symptoms and this can lead to excessive eating.
- Hyperthyroidism where the thyroid gland is overactive and the metabolism increases leads to an increase in hunger and food requirements.
- Diabetes mellitus where the blood glucose levels are uncontrolled due to a lack of insulin or unresponsiveness of the body to insulin.
- Hypoglycemia where the blood glucose levels drop to very low levels requiring a person to consume food to restore normal levels.
- Gastritis where there is inflammation of the stomach wall which is aggravated by stomach acid. Food may help to relieve the discomfort. The symptoms of gnawing stomach pain may be mistaken for hunger.
- Peptic ulcers are open sores in the wall of the stomach or duodenum. Eating may provide short term relief of symptoms thereby leading to overeating.
- Mental health disorders like depression or anxiety where food is a source of comfort and there may be disruptions in appetite control as a result of the underlying mental condition.
- Eating disorders such as bulimia nervosa where a person may binge eat and then purge by inducing vomiting.
- Intestinal parasitic worms like a tapeworm can lead to increased eating as the body is robbed of certain nutrients but excessive hunger and eating are not common symptoms in these infestations.
A number of different substances can disrupt appetite control, stimulate hunger, aggravate digestive conditions like gastritis or impair a person’s ability to determine whether they are eating exessively. This includes:
- Certain prescription drugs
- Over-the-counter medicines like aspirin which may lead to gastritis or ulcers
- Illicit substances, particularly marijuana