Everyone knows that food is necessary for survival, but good food is necessary for a healthy life. When you eat nutritious food, you are providing your body with the things it needs—vitamins, minerals, antioxidants and so on. But, when you eat processed foods or diets devoid of fruits or veggies, you are putting yourself at risk for a host of mental and physical symptoms, which can lead to chronic illnesses.

So, what are the short-term symptoms of a bad diet?

1) Tiredness

You’re probably familiar with the feeling you get after chowing down half a bag of family-sized chips or a combo at your favorite fast food establishment. It may be satisfying at first and you may receive a short burst of energy from bread or soda, but this is typically followed by a burnout. High-fat foods, on the other hand, give us longer-lasting energy, but put a strain on our digestive system. This reduces oxygen levels in our brain, leading us to feel tired and worn out. It also leads to trouble focusing on tasks at hand.

2) Heartburn

Heartburn is a very uncomfortable, sharp pain in the chest area. Unfortunately, it is very common among individuals in North America, thanks to a diet high in fat and oils. Fried foods, chocolate and high-fat dairy products are all culprits of heartburn.

3) Sugar Cravings

When you eat sugar, dopamine (the “feel-good” hormone) is released. This makes you crave even more sugar. In addition, insulin is secreted, causing the cells to take up the glucose from blood. This leads to swings in blood sugar levels, which can make you feel tired.

What kind of damage does it cause over the long term?

It’s important to realize that everything you put into your body affects it, especially if consumed over the long term. The following list of consequences of a bad diet is not exhaustive.

1) Chronic Diseases

If you constantly eat sugar, your cells may become insulin-resistant (meaning they don’t respond to insulin). Your body then requires higher levels of insulin to take up glucose. This state is known as pre-diabetes and it leads to diabetes if not managed effectively. On the other hand, eating too much processed foods and not enough healthy foods with antioxidant or anti-inflammatory properties may cause your body to become chronically inflamed. This can manifest itself as rheumatoid arthritis, multiple sclerosis etc. Inflammation is also a risk factor for cancer.

As mentioned above, heartburn is common in North America. But, if you’re experiencing heartburn often, you may have gastroesophageal reflux disease (GERD). This condition may cause tissue damage in the esophagus and is a risk factor for esophageal cancer.

2) Obesity & Cardiovascular Disease

If you eat too much sugar over the long term, it raises your risk of obesity. Your liver typically metabolizes sugar for energy, but if there is too much sugar, it gets stored as fat. Eating unhealthy fats (such as saturated and trans fat) also raises your risk of obesity and increases your LDL (“bad”) cholesterol. There are a host of disadvantages to being obese, but one of the most serious is the high risk of cardiovascular disease (CVD).

3) Depression

Sugar can increase stress hormone levels in the brain. As you can imagine, this is a very bad thing (who needs more stress?). A study showed that when placed in the same maze, mice fed a high-sugar diet gave up sooner than mice fed a healthy diet. Giving up is a sign of depression. It may be really surprising to think that your diet can affect your mental health, but your body is interconnected. When you consume a particular food product, it has a chain effect.

4) Cognitive Decline

Over time, consuming too much sugar or junk food can be detrimental to your mind, as it leads to difficulty remembering and learning. One study showed that over the course of eight years, all the participants’ hippocampus shrank, but the obese participants’ hippocampus shrank the most. Studies have also shown that inflammation (which may very well be caused by a bad diet) is associated with an increased risk of Alzheimer’s disease and dementia.

Of course, not having enough essential vitamins, minerals and fatty acids also causes your brain to suffer. When your brain doesn’t get what it needs, it suffers from oxidative stress and cell damage.