Today’s prompt, and the companion piece behind it.

The Problem Foods

What combinations of nutrients trigger overconsumption by hijacking the brain’s reward system?

The Short Answer

The most problematic foods combine sugar, fat, and salt in proportions that one paper defines, by nutrient thresholds, as hyper-palatable. In a controlled trial, people ate 508 calories a day more on ultra-processed food without feeling any fuller. These foods are also often compared to addictive substances, and that comparison is less settled than it sounds. The body below says how much less. Understanding this helps you recognize which foods are easy to overeat, rather than blaming yourself for overeating them.

Something to Sit With

What foods can you not eat in moderation?

Are they whole foods, or processed combinations of fat, sugar, and salt?

What does that tell you about where the problem lies?

Learn More

The Hyperpalatability Formula.

Researchers define “hyperpalatable” foods as those meeting specific nutrient thresholds, combinations the authors say may facilitate overconsumption despite satiety.^[1] Fazzino and colleagues (2019) identified three key combinations:

Fat + sodium. More than 25% of calories from fat and at least 0.30% sodium by weight. Examples: bacon, cheese, most fast food.

Fat + sugar. More than 20% of calories from fat and more than 20% from sugar. Examples: ice cream, cookies, chocolate, pastries.

Carbohydrate + sodium. More than 40% of calories from carbohydrates and at least 0.20% sodium by weight. Examples: chips, crackers, pretzels.

The paper’s criteria did not capture any fresh or raw fruits, meats, or fish.^[1]

The Reward System Hijack.

Your brain evolved to seek calorie-dense foods in an environment of scarcity. When you find sugar, the dopamine system activates: “This is valuable, remember this, seek this again.”

In the ancestral environment, this served survival. Sweet things (ripe fruit) were safe and caloric. Fat (animal meat, nuts) was essential and scarce. Salt was critical for electrolyte balance.

Hyperpalatable foods exploit these circuits at industrial scale. Imaging shows reward-region activation patterns paralleling those seen in substance dependence. That is a blood-oxygen signal rather than dopamine, measured against a tasteless control rather than against natural foods, so it supports no comparison with whole food.^[2] How close that parallel runs in people is genuinely unsettled: the imaging results conflict, no addictive agent in food has been identified, and one review’s authors propose that processed-food addiction in humans is much more like caffeine or nicotine addiction than like cocaine or heroin.^[3] What Gearhardt and colleagues did measure is the pattern itself: in 39 young women, higher food-addiction scores tracked greater activation in reward regions while they anticipated a milkshake, and reduced activation, while they drank it, in a region the authors tie either to weaker inhibitory control or to a weaker satiety response.^[2]

Why Satiety Fails.

Natural foods come with built-in limits:

• An apple has sugar but also fiber, water, and bulk
• Meat has fat but also protein that triggers satiety hormones
• Whole grains have carbohydrates but also fiber that slows absorption

Hyperpalatable processed foods strip away these limits, and the effect has been measured directly. In a controlled trial, people ate 508 kcal a day more on an ultra-processed diet than on a matched unprocessed one, while reporting no difference in hunger, fullness or satisfaction, and none in how pleasant or familiar the meals were.^[4] The appetite hormones matched: PYY rose and ghrelin fell on the unprocessed diet; on the ultra-processed one neither moved.^[4]

Palatability itself runs against fullness. Across 38 foods tested at matched energy, palatability ratings correlated negatively with satiety: the more a food was liked, the less it filled.^[4]

The design story, that foods are engineered to dissolve before satiety registers, is Moss’s investigative reporting rather than a measured finding.^[4]

The “Can’t Stop” Experience.

If you’ve ever opened a bag of chips intending to have a few and finished the bag, you’ve experienced hyperpalatability. The “can’t stop” feeling isn’t simply weakness: it has a measurable neural signature, heightened anticipation paired with the weaker response during eating described above.^[4] Note what that shows and what it does not: it measures the response, in 39 young women, cross-sectionally. It does not establish that the foods were designed to produce it.^[4]

The sequence:

1. First bite triggers reward response
2. Reward response creates desire for more
3. Satiety signals are weak or absent
4. Continued eating increases reward-seeking
5. Stopping requires active resistance against neurobiology

This is fundamentally different from eating an apple and stopping when satisfied. With whole foods, stopping is natural. With hyperpalatable foods, stopping requires overriding the reward system.

Practical Implications.

Recognition. Identify which foods in your environment meet the thresholds above. Usually they’re packaged, processed, and combine multiple reward triggers.

Avoidance at the source. Not having these foods in your home is easier than resisting them once they’re present. The decision happens at the store, not at the pantry.

Compassion for “failure.” If you overeat hyperpalatable foods, understand that eating more of foods like these is the measured response. You’re not weak; you’re responding the way the people in that feeding trial did.

Whole food defaults. When your baseline eating is whole foods, you’re working with foods that have natural stopping points. Satiety functions as intended.

Further reading:

• Fazzino TL, Rohde K & Sullivan DK, “Hyper-palatable foods: Development of a quantitative definition and application to the US food system database”^[5] — Obesity, 2019
• Gearhardt AN et al., “Neural correlates of food addiction”^[6] — Archives of General Psychiatry, 2011
• Moss M, Salt Sugar Fat: How the Food Giants Hooked Us^[7] (2013) — On the food industry’s manipulation of processed foods
• Kessler DA, The End of Overeating^[8] (2009) — How food is engineered for craving

Written by AI, directed and approved by me. How this is made →