Processed Foods and Metabolism
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Why Are Processed Foods Bad For Metabolism

The term Processed foods applies to any kind of food that has been altered from its natural state either for convenience or for increasing its shelf life or to reduce post-harvest losses. We live in a world where processed foods are easier and cheaper to come by than healthy whole foods. Research has shown that nearly 60% of food purchased is highly processed foods.

Though some amount of processing is required to ensure the safety of perishable foods like dairy and meat products, highly processed foods are said to be bad for your health, primarily because they slow down metabolism and give rise to many health conditions. Ingredients such as salt, sugar and fat sometimes are added to make the flavour more appealing or to help give it longevity that can lead to weight gain, diabetes and high blood pressure. Also know about curd with sugar benefits.

Are processed food good or bad for metabolism

What Are Processed Foods?

 The term ‘processed’ may not technically always be accurate since there is some kind of processing that happens to all kinds of food. There are different kinds of processing and when you want to know what processed foods to avoid, you essentially want to know about chemically processed food. These foods often only consist of refined ingredients that are filled with adulterated and artificial substances with minimal nutritional value. A large number of chemical agents like flavors, colors, sweeteners, etc are added to these foods to be able to preserve them for larger periods of time. These are sometimes also called ‘ultra-processed’ foods or ‘cosmetic’ foods.

But are these processed foods healthy? Since they taste good, are readily available, and are not very expensive, they are often bought frequently. However, these foods contain less dietary fiber and much fewer vitamins than whole foods, hence causing significant weight gain and other heart diseases. Read more to know about what level of blood sugar is dangerous?

Are All Processed Food Unhealthy?

No! There are Two Ways that Foods can be processed: Mechanical and Chemical.

  1. Mechanical : If only mechanical processing is done to a food with no added chemical, then it is still the real food and can be beneficial and play an important role in meeting the demands of a balanced diet. For example, pasteurized milk, boiled vegetables, and butter which is cream that has been separated from the milk and churned to get the final product are all processed yet healthy.
  2. Chemical : The second type of processing is chemical processing, which is what we should be more concerned about unhealthy processed foods. This is because chemically processed foods, contain refined ingredients and other artificial substances that alter a product’s taste, health, and properties. They contain flavouring agents, colour, and sweeteners, all of which have little or no nutritional value and cause more harm than they give benefits.

What Are the Types of Processed Foods?

To understand the processed foods better, NOVA classification system is used that splits foods into four broad categories:

  1. Unprocessed or Minimally Processed Food : These foods usually undergo mechanical processing. They are usually dried, crushed, filtered, grounded, powdered, blanched and chilled, heated, etc. We use many such foods in our daily life, including milk, frozen vegetables, packed curd, mushrooms, nuts, eggs, spices and herbs, raw cuts of meat, cleaned fish, etc. These minimally processed foods are suitable for travel, transport purposes or to increase the shelf-life of the product. This food group forms the mainstay of a healthy, nutritious diet, and a major chunk of your grocery cart must contain foods from this group.
  2. Processed Culinary Ingredients : This group of foods contains ingredients that help you cook and often cannot be eaten all by themselves. Calorie-dense ingredients like oils, butter, sugar, and non-caloric ingredients like salt are an integral part of this group. Processed seed oils contain high omega-6 fatty acids that have been linked to an increase in triglycerides and LDL, both harmful to your cardiovascular system.
  3. Processed Food : When you combine the first two groups of foods such as baked beans in brine, canned fish in brine or fruit pulp preserved in sugar syrup, it creates foods with increased shelf lives. Checking the label of the food will help you know how the food has been packed. While some of these foods can be acceptable in your diet, it all comes down to the ingredients used in the product. When foods do not contain added sugar, salt, emulsifiers, or additives, they are considered not excessively processed but still healthy. However, the biggest risk with this group of foods is components like sugar that are hidden in different forms.
  4. Ultra-processed Food : This group of processed foods are by far the most dangerous to your metabolic and overall health. These foods are easily found in all stores, extremely cheap, and the various additives make them very addictive. Think of things you tend to munch or binge on! Products like energy bars, energy drinks, ice creams, biscuits, cereals, crackers, nuggets and many more. Manufacturers of these products create them by combining natural foods with synthetically created ingredients like preservatives. Also know about sugar free biscuits.

How are Processed Foods Manufactured?

The usual process to manufacture any ultra-processed food item is as below.

  • Step 1 : First, whole foods are broken down to create components like oil, proteins, fibre, sugar, etc.
  • Step 2 : Trans fats in these foods are created by a chemical process.
  • Step 3 : Next, these products face chemical modifications that break them down further.
  • Step 4 : Synthetic additives and food derivatives are then added to them, and Voila, your ultra-processed food is ready!

This manufacturing process clearly shows how the whole foods were modified and lost their original nutrients and health. A host of studies and research conducted has associated ultra-processed foods with a 39% increase in obesity and a 79% increase in metabolic syndrome.

Effects of Processed Foods on Metabolism

It is now clear that processed foods do no good to us and our health. In fact, they cause more harm. Here’s how processed foods impact your metabolism and what processed foods do to your body.

  • Increase insulin resistance and inhibit insulin sensitivity
  • Disrupt liver function
  • Cause oxidative stress in the body, the biggest reason for cancer
  • Cause an imbalance in the gut microbiome, causing GI disturbances
  • The trans fats added during the industrial manufacturing of foods promote inflammation in the body and increases cellular stress.

Excessive or Ultra Processed Food

Risk Factors and Warning Signs

Due to the above harmful effects of processed foods, people who consume a large amount of these foods causes conditions like Obesity and Metabolic syndrome. If you have three or more of the below mentioned risk factors, you may be eating a lot of processed foods.

  • Increased waistline
  • High triglycerides or on medication to lower their levels
  • Low HDL(good cholesterol) and high LDL(bad cholesterol)
  • High blood pressure
  • High fasting blood glucose or require medication to bring the high blood glucose under control
  • Anxiety and depression
  • Cancer

Bottom Line

Avoiding ultra-processed foods is a great way to tweak your existing lifestyle and make it a healthy one. Reading product labels before buying processed foods can guide you to eating healthy, minimally-processed foods. It may be impossible to eliminate processed foods from our diet altogether but taking the step to minimize their consumption can make a world of difference to your health. Taking a break from processed foods can bring your parameters on track and can help reverse conditions like obesity, type 2 diabetes, high cholesterol, hypertension, among others.


1. Can eating processed food cause Insulin Resistance? 

While there is no causation study to prove this aspect, there is surely a correlation. This could be because processed food is high in carbs and sugar which increases the body’s requirement for insulin. It also increases the weight and fat that makes it tougher for insulin to reach the different muscles and bloodstream, causing resistance. 

2. How does Processed Food affect people with Diabetes?

All the characteristics in food that a person with diabetes should be avoiding are present in processed foods – high sugar, high carbs, low nutrients, low fiber, a great number of calories, high trans fats, etc. This simply means that these foods have a high glycemic index causing the sugars to spike high and fast. A person with diabetes should be avoiding processed food to the maximum. Read more about what foods to avoid with diabetes.

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This website's content is provided only for educational reasons and is not meant to be a replacement for professional medical advice. Due to individual differences, the reader should contact their physician to decide whether the material is applicable to their case.