Is Junk Food Slowing Down Your Metabolism?

Some foods increase your metabolism, but junk food could actually be slowing it down, causing even more weight gain and making it harder to lose weight in general.

With roughly one-third of adults in the United States with a body mass index (BMI) of over thirty, there’s no doubt that poor nutrition habits have a great impact on overall health and longevity.

To reverse any damage that has been incurred, and to prevent diseases from developing, it is in our best interests to adopt healthier eating habits and maintain a more active lifestyle.

Studies have shown that over-consumption of junk food is associated with obesity and metabolic dysfunction. (1) It has also been shown to increase risk factors for other diseases.

The Effects of Junk Food on Your Metabolism

When you consume food, your body digests and metabolizes the food to create energy. Simply metabolizing proteins and other nutrients found in healthy food burn calories. This is referred to as the thermic effect of food. Junk food however, is the opposite.

It takes less energy for your body to metabolize and store junk food, which tends to be high in fat and carbohydrates, as compared to healthy food which tends to contain more protein.

A recent study monitored two groups of people – one group consumed a high protein diet and one group consumed a high carbohydrate diet.

The body temperature and nitrogen balance were both raised in the group that consumed the high protein diet. These results indicated that their body was working at a higher energy level, therefore burning more calories.

Overall, this leads to fewer calories being burned throughout the day, making weight loss and weight management more difficult. (2)

The Effects of Junk Food on Your Insulin Levels

Fast food consumption in the USA has increased over the past few decades, and so has the risk of type 2 diabetes due to changes in bodyweight and insulin resistance.

In a recent study done on individuals and their fast-food consumption, researchers found that those who ate fast food frequently (more than twice a week) had a two-fold greater increase in insulin resistance than those who consumed fast food less than once a week. By developing a resistance to insulin, your body is not able to appropriately maintain your blood sugar, making you more susceptible to type 2 diabetes.

The conclusion of the study suggests that fast food increases the risk of obesity and type 2 diabetes. (3)

The Correlation Between Junk Food and Food Addiction

Your urges to eat and your cravings are influenced by stimuli found in the environment that are associated with food cues. While food cues affect everyone, obese individuals are more sensitive to food cues. Those individuals report stronger cravings and often report consuming larger portions after food cue exposure.

Researchers have found that the expression of the receptor for food cues is enhanced by the junk food diet. The increased expression of the receptor leads to being more sensitive to cravings, and more susceptible to obesity.

The increased expression of the receptor also makes you more sensitive to motivation to eat more and food addiction. (4)

The Effects of Junk Food on Academic Performance

Aside from weight gain and metabolism inhibition, junk food can also negatively affect your academic performance.

Regular breakfast consumption, combined with global diet quality meals and global diet quality meal patterns are associated with positive academic achievements. Whereas, junk food, fast food and nutrient-deficient foods are associated with negative academic associations.

Junk food leads to less energy and affects your ability to properly focus, inhibiting your ability to succeed accordingly in academics. (5)

The Effects of Healthy, Nutritious Whole Foods

Whole foods, with a large number of nutrients and a complex structure aid in overall health. By eating unprocessed foods, you are enabling your body to properly digest and absorb the nutrients provided by the food. This will aid in increasing metabolism and maintaining or losing weight. (6)

Diets rich in whole foods such as whole grains, low-fat dairy products, fruits and vegetables, in combination with a diet low cholesterol, refined sugars, refined grains and saturated fats, has been found to improve weight loss, DMI and fat mass. (7)

Studies have found that by consuming more fruits and vegetables, you are also more likely to consume other items of greater nutritional value – such as milk or water, as opposed to soda or alcohol. (8)


Eating habits – both what you eat and when you eat it – have a great impact on your overall health and weight management. Multiple studies have found several negative effects of frequent junk food consumption including weight gain, lower metabolism and increased risk of type 2 diabetes.

Frequent junk food consumption has also been linked to increased cravings and the likelihood of overeating or binge eating. Junk food triggers the expression of a food cue receptor, which can increase your cravings for more junk food – only worsening the effects and increasing your consumption.

Junk food has also been found to negatively affect other aspects of your life and body functions, such as academic performance. The components of junk food lead to you being sluggish and unable to focus appropriately, therefore, hindering your ability to perform at your optimal level.

In contrast, whole, unprocessed and natural foods provide optimal nutrients that allow for the maximum absorption by your body. A healthy, whole food diet will provide you with maximum energy, nutrients, and increased metabolism, enhancing weight loss and weight management.

Overall, junk food does not offer any health benefits and does not improve your performance in any aspect. While it might taste good sometimes, it only leads to the increased consumption of more junk food – still not offering you anything beneficial.

A diet consistent of whole foods will allow your body to function at its prime and will make you feel much better.

Poor nutrition is responsible for more deaths than alcohol, tobacco and low-level physical activity combined.

While some people report that healthy food is more expensive, health care for ailments that stem from not eating healthy can end up being just as expensive or even more expensive than it would be to just eat whole, healthy foods in the first place.

Search Healthy Hints