How does a bad diet affect the body?

What is a Bad Diet Doing to Our Bodies

It’s common knowledge that eating a high-fat, high-sugar diet that is heavy on processed foods and low on nutrients is unhealthy. But do you know why? This article explains what a bad diet is doing to our bodies.

One in five deaths around the world are linked to a poor diet, with associated diabetes and cardiovascular disease the key risk factors, according to the September 2017 released Global Burden of Disease Study (GBD).

While smoking killed 7 million people globally in 2016, bad diets killed 10 million, largely because they did not eat enough whole grains, fruit, vegetables, nuts, seeds and fish oils.

Poor nutrition might kill you in the long run but eating a fast food burger with chips and a sugar-laden soft drink also has immediate and mid-term negative effects on our mental and physical health and wellbeing.

If your diet is bad, expect to be more tired, more stressed and have reduced brain function and capacity to work than your healthy-eating friends.

In fact, consuming just one high-fat, high-sugar meal leads to blood vessel inflammation and immediate detrimental changes to the nervous system according to a research paper in the Journal of the American College of Cardiology.

Speaking to TIME Magazine, the study’s lead author, James O’Keefe said “Your health and vigor, at a very basic level, are as good as your last meal.”

He cited a spike in sugar levels from bad diets as causing immediate bodily inflammation, blood vessel constriction, increased blood pressure and the generation of free radicals that cause chronic disease and ageing.

A few hours later, when your blood sugar plummets because the food eaten does not contain sustained-release energy, expect to feel lethargic and hungry again. And the cycle continues.

Conversely, if you eat an unprocessed, high fibre diet full of plant-based foods, whole grains, legumes and nuts you will avoid the blood sugar spike and feel full for longer, thanks to their slow release energy characteristics.

If you keep eating junk food, in only five days you will begin to alter your metabolism and affect your muscles’ ability to oxidize glucose and respond to insulin – which is a risk factor for diabetes and other diseases, according to a study by Virginia Tech.

Diet Change Challenges

Those who have been consuming a bad diet are unlikely to feel satisfied when consuming healthier foods, meaning a transition to a healthy diet may be initially challenging.

“The more you eat it [junk food] the more you crave it. It becomes a vicious cycle,” O’Keefe told Time.

There is also evidence that fatty, sugary foods promote the excretion of cortisol, a stress hormone that further stimulates your appetite for calorie-dense foods.

O’Keefe encourages people to get a home glucose monitor so they can immediately see what their meals are doing to their body.

“It may help you stick to your plan to eat well…You can improve your health, basically, from hour to hour.”

Bad Diets Lead To:

  • Premature death
  • high cholesterol
  • heart disease and stroke
  • type-2 diabetes
  • osteoporosis
  • some cancers
  • depression
  • high blood pressure
  • Reduced brain function
  • tooth decay
  • eating disorders
  • being overweight or obese


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