Sue's Blog

Ultra-processed foods linked to obesity

Our readers have been telling us for years that they lose weight when they switch from the typical Western diet to failsafe eating.

“We are just amazed how much healthier our 8 year old son has been since trying to be failsafe. Have you ever looked into the relationship between additives and obesity? Since being on the diet my children's appetite has diminished incredibly. Simply because they no longer have cravings and feel hungry after eating a meal …  “ –  from story [1175]

A world-first study published last week agrees. 

  • Researchers kept 20 healthy adults in a clinical research centre where they were randomly assigned to ultra-processed or unprocessed diets for 14 days followed by 14 days of the alternate diet
  • The diets were matched for presented calories, sugar, fat, fibre and macronutrients
  • Participants could eat as much or as little as they liked – and they ate about 500 calories a day more on the ultra-processed versus unprocessed diet
  • On average, participants gained nearly half a kilo a week on the ultra-processed diet and lost nearly half a kilo a week on the unprocessed diet (see graph)


During the unprocessed diet, the appetite-suppressing hormone PYY increased, and the hunger hormone ghrelin decreased. Researchers do not know which aspects of ultra-processed foods caused the difference.

The researchers concluded:

  “limiting consumption of ultra-processed foods may be an effective strategy for obesity prevention and treatment”

Other studies have linked various food additives to obesity, including MSG (see MSG & belly fat) and propionate bread preservatives (see Bread preservative linked to obesity and Caution: cultured dextrose).

More reader stories

“I’ve been failsafe for 5 years. I’ve noticed that I lose weight on failsafe eating and gain weight if I go off it …  I think it’s due to the additives. I think they make you eat more …” - attendee at our 2016 Roadshow

“I lost 13 kg in 3 months when I started failsafe. I think it’s because of avoiding processed food (I do home cooking now) and also I went dairy free. My lifelong asthma also went away “ – attendee at our 2016 Roadshow

“We are doing the elimination diet for my three children. I have been on the diet too  … The best thing is I am not craving sweets and the weight is dropping off me!! I am losing about half a kilo a week (except during the salicylate challenge).” – from story [212]

“… I avoid all processed foods, eat failsafe at home, and make informed choices when out. I love wine but have cut down to a couple of glasses per week, have decaf coffee, soy milk etc …  I'm a bit evangelical when I tell people why I've lost so much weight …” – from story [102]

“… following the diet ... I have new hope for losing weight. I've had food cravings go away entirely for the first time as an adult …"   – Laura from story [1524]
“I had to give up all food additives and chemicals at the age of 55 because of the physical and mental problems they were causing me. Now I just eat veggies and fruit. Nothing else. I lost 137 pounds (62 kg) in 18 months … As Jack LaLanne always said... ‘if man made it...don't eat it.’"  - Tim from story [1269]

How failsafers avoid ultra-processed foods

“I find shopping and cooking easier as I skip most of the aisles and cook with fewer foods. The grocery bills are cheaper …  “ – story [211]

“We have gone back to the old fashioned make-it-at home cooking and baking  …” - from story [035]

“I feel very comfortable with this diet and am not craving anything … I emptied the pantry and fridge of everything that wasn't failsafe and gave it all away.. I cook our biscuits and cakes and meals, of course, and it just feels right. Going to the supermarket feels good - 'no, nothing in this aisle'....... 'no, nothing in this aisle'......  and saving at the checkout! You didn't mention that the failsafe diet was also cheap! …  it is the simplicity that I like most …” - from story [369]

The science

Hall KD et al, Ultra-Processed diets cause excess calorie intake and weight gain: an inpatient randomized controlled trial of ad libitum food intake. Cell Metab. 2019 May 16. pii: S1550-4131(19)30248-7.

More info

Blog Bread preservatives linked to obesity

Blog Caution: cultured dextrose

Blog MSG & belly fat

How to start failsafe eating

Factsheet on failsafe weight loss