How food processing starves our bodies of nutrients, leaving us feeling run down and tired

10 October 2023

Processed foods might satisfy your taste buds, but they can lead to a number of chronic health conditions, especially when you eat them regularly over longer periods of time.

It is no exaggeration to say that food processing is a double-edged sword. While processed foods provide an affordable and convenient source of sustenance, they also come with several potentially serious health consequences.

This article looks at processed food and how modern production methods destroy many of the nutrients in the food we eat.

What are processed foods?

The National Health Service (NHS) defines processed foods as any food items that have been altered during preparation.

We can break food into four categories:

There are four types of food:

1/ Unprocessed and minimally processed – these are raw ingredients like fruit, vegetables, nuts, seeds, eggs, unprocessed meat.  Minimally processed food may have been dried, crushed, roasted, frozen or boiled, but contain no added ingredients.

2/ Processed culinary ingredients: includes oils, fats, sugars and salt.  These are either eaten alone or with

3/ Processed foods – these are made with a mix of ingredients from group one and two ingredients.  These include smoked or cured whole meats, fresh bread, tinned fruit in syrup, beer and wine. The main purpose of processing is to prolong the food’s life.

4/ Ultra-processed food – a simple rule is to consider that these foods contain ingredients that you wouldn’t use in home cooking.  These include chemicals, colourings, sweeteners and preservatives. 

Industrialised bread, pre-packaged meals, breakfast cereals and reconstituted meat products such as sausages.  And of course, soft drinks, confectionary, pastries, sauces and dressings.

Advantages of processed foods

The three key benefits of processed foods are:

  1. Convenient

You may find it challenging to spend substantial time on purchasing and cooking foods. It could be due to work pressures, commuting, or the need for recreational/family time. Studies show that the time people spend making food has decreased over the last decades.

Ready meals and processed foods are quick and easy after a long day or to go in a lunch box in a hectic morning.  Busy parents who may not know how to cook themselves and are not equipped to pass on the knowledge to their children.

For people eating alone, it is not easy to prepare a home cooked meal for one, and processed foods are much easier and offer variety.

  1. Cheap

Mass production means food processing companies can feed a lot of people at an affordable price. Manufacturers buy raw materials in bulk and employ efficient processing operations. All these factors contribute to a significantly decreased cost.

A Reuter article in 2022 reported that many British households had switched to unhealthy but less expensive foods due to inflation and rising food costs.

Between 2021 and 2022, the average price of vegetables and fish rose by over £8 per 1,000 kcal in Britain, whereas the increase was just £3.

  1. Accessible

When you are hungry, you are less likely to bother preparing vegetables or prepare a substantial meal. Hunger can be driven by poor diet in the day, spikes in blood sugar from snacking on refined carbohydrates and the lows leading to cravings.  The hungry feeling means people are more likely to opt to have some quickly-prepared food, processed or a ready meal.

Accessibility is crucial to why people opt for processed foods rather than spend time preparing their meals. 

Processed foods and your health

One of the secrets to a longer, healthier life is a diet without a calorific surplus and one containing enough micronutrients. Sadly, processed foods are just the opposite, as they contain more calories but lack many essential nutrients.

They are loaded with salt, saturated fat, “trans” fatty acids, and sugar. In addition, they tend to be deficient in protein, zinc, magnesium, vitamins A, C, D, E, B12 and niacin.

According to the British Heart Foundation (BHF), processed meats and meat dishes account for 19% of salt in the UK diet. In perspective, only 6% of salt comes from vegetable dishes.

Several studies have linked higher consumption of processed foods to a number of health issues, including:

  • Obesity
  • Heart disease
  • High blood pressure (hypertension)
  • Breast and colon cancer
  • Premature death from all causes
  • Depression
  • Low energy levels
  • Type 2 diabetes

Dr Joel Fuhrman, from the Arizona and Nutritional Research Foundation, writes that consuming higher amounts of salt and sugar daily for years increases stroke risk.

Processed food consumption in the UK

Over 50% of total calories in the UK diet comes from ultra-processed foods, reveals a 2019 article in the BMJ Journals.

The study, which involved over 9,000 participants, also found that free sugars accounted for 12.4% of total energy intake, above the recommended limit of 10%.

Notably, the UK ranks third among eighty high- and middle-income countries in terms of sales volume of ultra-processed food.

How food processing affects nutrition

Food processing involves one or more methods needed to turn fresh foods into food products. It also includes adding ingredients to enhance color, flavor, texture, appearance, safety, or shelf-life of the product.

Traditional food processing methods include:

  • Heating
  • Fermentation
  • Pickling
  • Smoking
  • Drying
  • Curing

Modern methods include:

  • Pasteurisation
  • Ultra-heat treatment
  • High pressure processing
  • Modified atmosphere packaging
  • Canning
  • Freezing

Effects of food processing on vitamins

Vitamin loss during processing can vary depending on:

  • Processing method
  • Type of vitamin (water- or fat-soluble)

For example, blanching (scalding fruits/veggies for a short period) can cause up to 30% loss of vitamin C, 20% of riboflavin, and 10% of niacin. 

In contrast, heat treatment can result in a loss of up to 45% for vitamin C and 50% for thiamine. Fat-soluble vitamins—A and D—are typically stable.

Likewise, most vitamins are stable during freezing and no significant loss is expected. 

Effects of food processing on minerals

Unlike vitamins, minerals are resistant to degradation by heat, light, or pH. Nonetheless, some minerals may be removed during processing (leaching) or added from the instruments used during processing.

Milling, a process to dehull and grind grains, can cause a significant loss of minerals.

For instance, milling whole wheat into white flour can result in up to 86% loss of iron, zinc, copper, magnesium, and selenium.

Contrarily, fermentation enhances mineral bioavailability. 

Effects of food processing on carbohydrates

Carbs are more than just sugars; they also include healthy dietary fibers.

Blanching, canning, or boiling fruits and veggies causes a measurable loss of glucose, fructose, maltose, and sucrose. However, (insoluble) fibers appear to be resistant to such losses.

Milling grains into refined flours also causes a loss of healthy dietary fibers.  Dietary fiber slows down the passing of food through the gut, it also makes us feel fuller for longer (important to avoid snacking)

Does cooking affect the nutrient content of foods?

Yes.  Cooking usually causes a loss of vitamins and minerals, such as potassium, magnesium, sodium, and calcium.

Microwaving for short periods is a way to preserve nutrients. When cooking with other methods, it is best to use as little water as possible.

Limiting processed foods promotes health

According to a large study in British adults, lowering the consumption of ultra-processed foods may help prevent and reduce the risk of cancer.  Processed meats containing nitrates are linked to bowel cancer, that includes foods such as sausages and bacon.

Key Takeaways

  • Processed and ultra processed foods are everywhere.  Cutting them out from our daily diet may seems unrealistic or even regressive, but the more natural foods we have in our diet, the better
  • Some essential nutrients, notably vitamins and fibers, are lost during processing.
  • A diet high in processed and ultra processed food has less room for unrefined foods such as vegetables and contain less dietary fiber.
  • Ultra processed foods have high quantities of sugar and salt and increase the risk of heart disease, obesity, type 2 diabetes, and certain cancers. 

Everything in moderation.  If your diet is a daily intake of processed and ultra-processed food, it is time to think seriously about the long term consequences to your health and quality of life.  That includes the future but also the present where more energy helps us cope with the challenges of life.

If you are not a confident cook, start simple.  Tray bakes, simple recipes from chefs like Jamie Oliver can make meal times fun.  Batch cooking, that is preparing meals and freezing them, means you cook once and eat often.  It’s like a ready meal but without the bad stuff and it is likely to be more nutritionally complete.

If you have children, experimenting with cooking is a great way to do things together whilst giving them a skill for life. 

The world is full of flavour and discovery after all.  And it is a way to get away from screen time!  When we think of happy times, it is usually being connected with others, eating with others.

Lastly, if you eat more unprocessed or minimally processed foods, not only will you feel better, you are also likely to make better choices towards your health generally, from going for walks to more vigorous exercise and activities … which can also be fun!

Our motto is eat healthy stay active.  (With a little what you fancy from time to time).