What Research Says About Processed Food + List Of Foods To Avoid (And Include)

Written by , BSc, Professional Certificate in Food, Nutrition and Health Ravi Teja Tadimalla BSc, Professional Certificate in Food, Nutrition and Health Experience: 8 years
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According to The American Journal of Clinical Nutrition, 61% of your daily calories could be coming from highly processed foods (1). And these foods, as per strong research, are responsible for nearly all the killer diseases of today (2).

If you are reading this article, chances are you had some form of processed food today. And this doesn’t come as a surprise, given that 7 out of every 10 foods that we touch on a daily basis are altered by chemical ingredients. But does this mean most of us are destined for premature death? Or is there a way out?

Table Of Contents

  1. What Are Processed Foods?
  2. What Makes Processed Foods Good Or Bad?
  3. What Are The Dangers Of Processed Foods?
  4. What Are The Processed Foods You Must Avoid?
  5. How To Choose Healthier Alternatives?

What Are Processed Foods?

Processed foods are those laced with unhealthy chemicals that contribute to diseases like cancer and obesity, right? Well, not quite. The definition is slightly complex.

Food processing is of three types:

  • primary food processing, which turns raw agricultural products into edible foods (like shelling nuts, or even butchering animals for meat)
  • secondary food processing, which creates everyday foods from ingredients that are ready to use (like baking bread), and
  • tertiary food processing, which involves the commercial production of ready-to-eat or heat-and-serve foods (the typical junk food).

Some common examples of processed foods include breakfast cereals, bread, meat products like bacon, sausage, and ham, cakes and biscuits, soft drinks, and convenience foods like ready-to-eat meals.

Even milk and seed oils are processed.

Does this mean you cannot eat any of those?

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What Makes Processed Foods Good Or Bad?

Not all processed foods are bad. Take milk – it is processed to remove the impurities. Seeds undergo processing too – they are pressed to extract oils, which can be sold in usable forms.

It is tertiary processing we must be wary of. Also called chemical processing, this is where foods are laced with additives and preservatives to make them look and taste appealing – and even to extend their shelf lives. These are typically what we call processed foods.

There are different methods of food processing. These include:

The MethodWhat Happens
CanningFood is heated to high temperatures and then stored in airtight containers.
FermentationSugars are broken down using bacteria or yeasts.
FreezingFood temperatures are reduced below -18°C to reduce harmful bacterial activity.
Modified atmosphere packagingAir inside a package is replaced by a gas mix (oxygen, CO2, and nitrogen) to extend shelf life.
PasteurizationFood is heated to 72°C to kill microorganisms and then rapidly cooled to 5°C.
SmokingFood is treated by heat and chemicals to preserve it.
AdditivesFood additives are added to preserve freshness, improve taste and appearance, and extend shelf life.

Almost all foods that we eat are processed to some degree.

And processing can work both ways – it can increase the nutritional quality of foods or even decrease it.

Beneficial processing is when foods are fortified with vitamins and minerals, or when fat, sugar, or sodium are reduced. On the other hand, excessive heating or freezing of foods can destroy important nutrients and even introduce undesirable substances into the foods.

This is what makes processed foods good or bad. But most often, foods that are processed tend to lean towards the ugly side. This is because of the ingredients that go into them. These include:

Artificial sweeteners, which enhance your appetite and provoke you to eat more. Animal studies have proven that artificial sweeteners can lead to weight gain, bladder cancer, brain tumors, and several other health hazards (3). Some lethal artificial sweeteners include aspartame, saccharin, and sucralose.

Trans fats, which are added to fried foods, store-bought baked goods, crackers, and chips. Research shows trans fats can cause cardiovascular disease (4). Trans fats may also lead to cancer, inflammation, a suppressed immune system, and diabetes.

Artificial flavors and colors, which are added to enhance the taste and appearance of foods. Statistics show that in the US alone, food manufacturers add 15 million pounds of artificial food dyes to foods every year (5). Synthetic flavors and food colors are also associated with neurobehavioral hazards (6).

High-fructose corn syrup, which could be as deadly as alcohol – it can tax and damage your liver. HCFS is deadly. Studies show how it can contribute to severe metabolic disorders and even obesity (7).

And this is what a report by the American Society for Nutrition has to say:

“Growing research suggests that excess phosphorus in the diet, particularly in the form that is added for processing purposes, may increase risks of cardiovascular and bone disease, particularly in those who have kidney disease.”

Phosphorus is widely used as a food additive, and now we know what an excess of it can lead to (8). This is just the tip of the iceberg.

The food additives pile up into a heap as big as the hills. There are several thousand food additives. Though some are added to make the food safer, most serve the purpose of making the food more appealing (9).

All of this can lead to severe health concerns.

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What Are The Dangers Of Processed Foods?

1. They Are Loaded With Sugar

Or high-fructose corn syrup. These added sugars are empty calories. They provide energy but contain no nutrition. Studies show how taking too much of this can lead to dangerous issues with your metabolism – including type 2 diabetes and heart disease (10).

And here’s the cold truth – processed foods are responsible for 90% of added sugars in an average American diet (11).

2. They Contain No Fiber

The processing of foods removes most (or all) of the fiber in them. Fiber has several benefits – it feeds the friendly bacteria in the intestines and improves digestive health. It also eases constipation and promotes regularity (12).

3. They Are Designed To Be Addictive

Foods like chips and cookies are chemically altered so that eating them releases dopamine (13). This is one reason people find it hard to battle food addictions or keep away from junk food. Junk foods can hijack the biochemistry of the brain, making people lose control over their intake.

Now you know why you cannot stop with just one single chip.

4. Have High Sodium Levels

Excess sodium is a killer. Your body sure needs salt to function properly – which you already get from a well balanced diet. But excess sodium is added to processed foods to improve their taste and shelf life. According to the Harvard School of Public Health, excess sodium can increase the risk of high blood pressure and heart disease (14).

5. Are Very Low In Nutrients

When compared to whole foods, processed foods are quite low in nutrients. They also don’t contain the trace nutrients present in organic foods. You will only be piling on calories and sugar and sodium, with absolutely no nutritional value.

6. High In Trans Fats

Processed foods often contain cheap fats and refined vegetable oils, which get converted into trans fats due to prior processing. These fats contain an excess of omega-6 fatty acids, which lead to inflammation and a host of other diseases (15).

Definitely not a pretty picture. So, what’s the next step? Understanding which processed foods you must avoid and which you can take.

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What Are The Processed Foods You Must Avoid?

Processed foods sure are convenient. But with this convenience comes calamity. The following table will give you some perspective.

Foods To AvoidAlternatives
Sugary or aerated drinksWater, soda water (with a slice of lemon, if desired), tea
PizzasHomemade pizzas with wholesome ingredients
White breadEzekiel bread, whole grain bread If you’re gluten intolerant, you can go for gluten-free bread.
Most fruit juices (due to the added sugar and removed pulp)Pulpy fruit juices with very little juice Eating whole fruits works best.
MargarineReal butter from grass-fed cows
Pastries, cakes, and cookiesHomemade cookies with healthy ingredients
Potato chips and French friesBoiled potatoes, nuts
Gluten-free junk foodsFoods that are naturally gluten-free, like plant and animal foods that are unprocessed
Low-fat yogurt (loaded with sugar to compensate for the lack of taste that fats otherwise offer)Full-fat yogurt with live and active probiotics, yogurt from grass-fed cows
Ice creamHomemade ice cream with healthy ingredients and less or no sugar
Candy barsA piece of fruit, real high-cocoa dark chocolate
Processed meatMeats from local sellers that don’t add too many unhealthy ingredients
Processed cheeseReal cheese
High-calorie coffee (one loaded with cream and sugar)Black coffee, coffee with some full-fat milk

We sure can make wise choices. Here’s how you can stop eating processed foods and opt for a much healthier lifestyle.

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How To Choose Healthier Alternatives

  • Make it a habit of reading food labels. You will know what is there in the processed food. Go for products without too much sodium, sugar, or trans fats.
  • Frozen and canned produce work fine. Frozen or canned fruits and vegetables are convenient, less expensive, and nutritious. Ensure you aren’t going for varieties with sugary syrups or salty sauces.
  • Be mindful while eating out. Preparing food at home is best. But if you want to dine out once in a while, why not? Go to restaurants that have healthier food choices. You can even check with the restaurant how the food is prepared. Opt for those where food is cooked fresh instead of packaged.
  • Grow fruits and vegetables. If you have space limitation, check for community gardening. Growing your own produce encourages you to stick to a healthier diet.
  • You can go for supplements too. Though not everyone may need a variety of supplements, research shows supplements can help bridge the nutrition gap (16). Ensure you go for organic supplements that come from reputed brands. You may also want to check with your health care provider if you have any specific medical condition/are already taking medications.

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It’s all about having the right information. Unhealthy processed foods sure form a major part of your environment, but that doesn’t mean you cannot avoid them. By being proactive and mindful about your choices, you can start living a healthier lifestyle.

Let us know how this post has helped you. Leave a comment in the box below.


  1. Is the degree of food processing and convenience linked…”. The American Journal of Clinical Nutrition.
  2. Origins and evolution of the Western…”. The American Journal of Clinical Nutrition.
  3. Sugar substitutes…”. Government Medical College, Gujarat, India. US National Library of Medicine.
  4. Trans fatty acids…”. Aga Khan University, Karachi, Pakistan. US National Library of Medicine.
  5. Food dyes: A rainbow of risks”. Center for Science in the Public Interest.
  6. Synthetic food colors and…”. University of Rochester, New York, USA. US National Library of Medicine.
  7. High fructose corn syrup induces…”. Queens College, New York, USA. US National Library of Medicine.
  8. Assessing the health impact of phosphorus…”. Oxford Academic Journal.
  9. Food additives”. World Health Organization.
  10. Adverse metabolic effects of dietary…”. University of California, USA. US National Library of Medicine.
  11. Ultra-processed foods and added sugars in the…”. British Medical Journal.
  12. Systematic review: the effects of fibre…”. Leeds Gastroenterology Institute, UK. Alimentary Pharmacology and Therapeutics.
  13. From passive overeating…”. International Scholarly Research Notices.
  14. Health risks and disease related to salt…”. Harvard School of Public Health.
  15. Cardiac proinflammatory pathways are…”. American Journal of Physiology.
  16. Should you take dietary supplements?” News in Health. US Department of Health and Human Services.
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Ravi Teja Tadimalla
Ravi Teja TadimallaSenior Editor
Ravi Teja Tadimalla is a senior editor and a published author. He has been in the digital media field for over eight years. He graduated from SRM University, Chennai, and has a Professional Certificate in Food, Nutrition & Research from Wageningen University.

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