David Kessler claims in his latest book that he is average, admitting that he has been in a despairing battle with his own body, yo-yoing between fat and thin, all his life. Yet except for sharing this health-destroying weight problem with three-quarters of the American and two-thirds of the British populations, he is anything but average.
A former dean of two of US medical schools, Kessler was chief science officer to the White House for the Covid-19 pandemic, a period of overwork that led him to put on 40lbs. He also ran the US Food and Drug Administration for several years. While there, he famously took on the tobacco industry. So he is well qualified to argue it is not laziness or lack of self-control that he and others suffer from, but a food industry whose products are engineered to create addiction.
Kessler has explored the devastating effects of what he calls “ultraformulated” foods on our health before in his bestseller The End of Overeating (2009). These foods are not just “ultraprocessed” — the term recently coined to define junk foods — but artfully ultraformulated for mouth-feel, texture, colour and flavour to make energy-dense but nutrient-light combinations of fats, sugars and salt irresistibly palatable. He was not ready to call them addictive back then but he is now, with a new generation of weight-loss drugs shedding extra light on the mechanisms involved. In Diet, Drugs, and Dopamine, he gives a highly readable and persuasive account of the science behind this food addiction thesis.
Ultraformulated foods hijack the brain’s reward systems and its dopamine circuits. They alter the neurohormones that regulate the blood sugar response, and they disrupt those that tell us we are full. They thus cause highs and lows, cravings, and compulsive consumption. If we consistently eat too many calories, they end up being stored not just under the skin but as “toxic fat” in various non-fat organs including the liver, heart and pancreas, disrupting insulin production and increasing the risk of heart disease, stroke and diabetes.
Dopamine is also involved in memory so that if eating junk food has given us a dopamine reward hit before, say when we were distressed, we remember the cue and want it again, so the process can quickly lead to habitual behaviour.
Junk foods are now everywhere. To Kessler they are “the new cigarettes”. The man-made epidemic of obesity will not therefore be solved by exhorting people to greater will power to cut calories, although they do still have to do that. It requires instead a full battery of methods used to cure addictions — medication with weight-loss drugs during initial rehabilitation, then lifestyle changes and psychological treatments to maintain healthy weight.
Kessler has used the new drugs to shed his own excess successfully and sees them as game-changing, but with a huge caveat.
They work by mimicking a hormone that is produced naturally, Glucagon-like peptide hormone, or GLP-1, which stimulates the production of insulin in the pancreas after eating, and they were initially developed for diabetes treatment. Sold under brands such as Wegovy, Ozempic and Mounjaro, they work by slowing the movement of food out of the stomach and making people feel full. With GLP-1 receptors in the brain and gastrointestinal tract, they directly influence the sensation of satiety and reward, making it possible to lose drastic amounts of weight. But they are not a panacea — Kessler experienced some of the many side effects such as nausea, intense chills and abdominal pain. And when people stop taking them, without psychological treatments and lifestyle changes, they put weight back on.

A deep scientific understanding of the biological mechanisms involved, a former regulator’s pragmatism and a compassion born of personal experience make this an important contribution to the literature. Kessler notes the absurdity of one industry — the food sector — making us fat and sick only for another — the pharmaceutical industry — to develop lucrative drugs to treat that sickness. But, as he points out, “that is where we are right now.”
The underlying economic drivers that took us there are Stuart Gillespie’s subject in Food Fight. He places the current globalised food system at the heart of a cascade of interlocking crises: pandemics of obesity and undernutrition, climate breakdown, biodiversity loss, poverty and inequity.
Viewing food production through the lens of power, he traces its evolution through three regimes: colonial, cold war and corporate. The first was extractive, built on slavery and impoverishment of smallholders. The second encompassed the so-called Green revolution, achieved with seed breeding and fertilisers and pesticides that depend on the extravagant use of fossil fuels. In this cold war era, western agricultural subsidies were used as a tool of geopolitics, creating surpluses of a handful of crops — soya, wheat, corn, sugar — dairy and meat. These would become the cheap commodity ingredients for ultraprocessed foods, and for food aid provided postwar to allies. Gillespie’s third regime is the current structure in which a handful of transnational corporations dominate in each food sector and have become more powerful than individual nation states.

In many ways this is a synthesis of previous critiques. Gillespie acknowledges these — among them Geoffrey Cannon and Caroline Walker’s 1984 book The Food Scandal on the British diet, Raj Patel’s 2008 Stuffed and Starved on the inequities in the global food system, and Marion Nestle’s extensive work exposing the food industry as manufacturers of doubt and denial with their lobbying and regulatory capture.
Food Fight is an angry, tub-thumping polemic. If he comes at his subject with a passion that occasionally lacks nuance, it is because Gillespie has worked for decades for UN agencies and on international development research in rural India, Africa and South America. He has seen the devastating effects of power imbalances on the ground.
Diet, Drugs, and Dopamine: The New Science of Achieving a Healthy Weight by David A Kessler New River £22/Flatiron $32.99, 384 pages
Food Fight: From Plunder and Profit to People and Planet by Stuart Gillespie Canongate £20/Pegasus Books $29.95, 368 pages
Felicity Lawrence is author of ‘Not on the Label, What Really Goes Into the Food on Your Plate’ (2013)
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