Chapter 12
Lifestyle+ — 3
Figure 3.1. A randomized trial showed that participants who ate an ultra-processed food diet gained weight compared with those who consumed an unprocessed food diet and lost weight. Adapted from Kevin Hall et al., “Ultra-processed diets cause excess calorie intake and weight gain: An inpatient randomized controlled trial of ad libitum food intake,” Cell Metabolism 30, no. 1 (July 2019): 67–77 e3, https://doi.org/10.1016/j.cmet.2019.05.008.
It’s not just a matter of cardiovascular or metabolic or cognitive disruption. UPFs are associated with fatty liver disease, most types of cancer, sleep disorders, inflammatory bowel disease, depression, and dementia. A 62 percent increase in all-cause mortality is linked to more than four servings per day of UPF. This was echoed by a comprehensive review of forty-five studies involving a thirty-year follow-up of about seventy-five thousand women and nearly forty thousand men.
My friend Chris van Tulleken, a British physician-scientist who wrote the outstanding book Ultra-Processed People, conducted an experiment on himself. He increased his diet from 20 percent to 80 percent ultra-processed food for a month, with extensive baseline and follow-up assessments, including MRI brain scan and lab tests for lipids and inflammation. He gained fifteen pounds. As he put it to me, “There were enormous changes in connectivity between the habit, automatic behavior bits at the back in the cerebellum and the reward addiction bits in the middle of the limbic system and associated brain regions.” Chris’s hunger hormones went sky high, such as a fivefold rise in leptin, and there was a doubling of his C-reactive protein that tracks with body-wide inflammation. Being hungry and swollen doesn’t sound fun.
Chris and his identical twin have had whole genome sequencing that indicated they have many genomic variants that predispose them to obesity. However, when his twin brother, Xand, followed the same diet of ultra-processed foods, he got forty-four pounds heavier than Chris. That represented the biggest weight difference in the very large twin study conducted in the United Kingdom. Once again, it’s not all in the genes.
For healthy aging, UPFs must be restricted in your diet to the lowest level possible.
That’s why it’s so important to read labels and select items without additives, without added or fake sugars, with as few ingredients as possible. If there’s a health claim, beware. High UPFs are usually found in the middle aisles of grocery stores, which explains the helpful tip to do most shopping in the perimeter for fresh foods. When there’s a question, consider using the Open Food Facts app, developed in France with the help of tens of thousands of volunteers providing information for about three million substances.