The ultra-processed foods & weight gain connection

Processed foods weight gain

We’re told that weight is all about calories in, calories out – and that the simple solution is to eat less and move more.

The problem? The numbers don’t stack up. Official statistics show that, over the past few decades, the average number of calories people consume has dropped. The average daily energy intake in 1969 was 2570 kcal, but today, the average daily energy intake in the UK is around 1972 kcal.

During this time, average bodyweight has increased. Government statistics show that, in the UK, around 28% (1 in 4) of adults are obese, while a further 36.2% are overweight.

So if calories alone aren't to blame, what is? The causes of weight gain are many and complex, but one key factor is the overconsumption of ultra-processed foods.

56.8% of total energy intake in the UK is from ultra-processed foods

Did you know that the rise in obesity coincides with the increased consumption of ultra-processed foods? Think ready meals, instant soups, breakfast cereals, sweets and sugar-sweetened beverages, just to name a few. 

They’re highly refined and contain huge amounts added salt and sugar, but barely any fibre, vitamins, minerals and other essential nutrients that your body needs to stay healthy.

As well as being totally nutritionless, ultra-processed foods throw the body’s ability to maintain a steady weight (body weight homeostasis) completely out of whack. 

Your 'healthy' body weight range: Homeostasis

Body weight homeostasis is the body’s automatic system for weight control. Put simply, when a person starts to lose or gain weight, a host of processes begin in the body to return the person to their accustomed weight, often referred to as a ‘set point’.

Homeostatic control of body weight is thought to be influenced by many factors, including:

  • Hormones
  • Genetic influences
  • The gut microbiome 

But the body’s ability to regulate weight can be easily overridden by stress, sleep culture, personal food intake and the food environment we all live in. Crucially, ultra-processed foods can negatively affect 2 key players in weight regulation: hormones and gut health.

The result? Your body isn’t able to regulate weight as effectively as it should.

Ultra-processed foods negatively affect your hormones

A recent study examined the effects of an ‘ultra-processed diet’ versus an ‘unprocessed diet’ on healthy adults and confirmed how negatively ultra-processed foods affect the hormones that are part of body weight homeostatic control:

During the processed diet phase…

  • Blood sugar levels were higher > this can make you hungrier
  • Insulin secretion was higher > this can increase fat storage

During the unprocessed diet phase…

  • The appetite-stimulating hormone, ghrelin, decreased > they felt less hungry
  • The appetite-suppressing hormone, PYY, increased > again, they felt less hungry
  • Inflammation and cholesterol reduced during the unprocessed diet > their general health improved

These effects were observed only after two weeks, so it’s no surprise that ultra-processed foods have such a negative effect on both health and weight over the long-term!

Ultra-processed foods negatively affect your gut health

Research suggests that the gut microbiome – the bacteria that help you digest food and absorb nutrients – can significantly influence your ability to lose weight.

Diets that are high in ultra-processed foods are thought to cause ‘gut dysbiosis’. This when the bacteria in your gut become unbalanced, leading to an overgrowth of harmful bacteria and yeast. 

As well as increasing the risk of type-2 diabetes, heart disease, autoimmune conditions and cancer, gut dysbiosis is associated with weight gain and obesity. 

Why? Because your gut bacteria can affect how your food is digested, how fat is stored and how full vs hungry you feel. Together, these factors negatively impact body weight homeostasis (you body’s natural ability to regulate your weight).

What this means for you...

Ever tried cutting back on calories to lose weight, but failed to see long-term results? Ultra-processed foods might be holding you back. But by simply eating more whole foods and fewer processed foods, you’re likely to see a positive change – quickly!

We’ve evolved to eat, digest and absorb whole foods. They work in synergy with your hunger/satiety hormones, gut microbiome and other systems that help you to regulate your bodyweight (body weight homeostasis). 

They also take longer to digest and naturally keep you satiated for longer. For you, that makes it’s significantly easier to maintain a healthy weight.

Getting started could be as simple as...

  • Purition for breakfast
  • A healthy whole food snack or lunch
  • A Daily Feed meal for dinner (sign up for free weekly meal plans)

Need help kickstarting a healthy, whole foods diet or reducing the amount of processed foods in your diet? We’re here to help. Get in touch today by emailing or calling us on 01743 444 397.


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