Why 'Health Halo' Labels Trick You

The health halo is a mental shortcut. When a food carries one clearly positive attribute, your brain generalises it to the whole product. Low-fat becomes low-calorie becomes healthy becomes fine to eat a lot of. Each step is a small leap, and none of them is guaranteed by the original claim. A low-fat biscuit can be higher in sugar than the normal one. A natural snack can be pure ultra-processed formulation with a leaf on the box.

The reason it works is that reading and judging every food properly is effortful, so we lean on cues instead. Marketers know this, which is why the front of the pack is covered in the cues and the useful information is in small print on the back. The halo is not a personal failing, it is a designed effect.

It is also self-reinforcing. Once a food feels healthy, you are less likely to bother checking the back, which is exactly what lets the misleading claim survive. The glow from one word switches off the very scrutiny that would puncture it. That is why the fix has to be a habit rather than a one-off judgement, because the halo is designed to stop you looking twice.

This is the part that makes the halo genuinely costly. In a set of studies on fast-food branding, people estimated that a meal from a chain positioned as healthy had far fewer calories than the same meal from a chain positioned as indulgent. Then, having judged the main dish as virtuous, they were more likely to add a high-calorie side, drink, or dessert, wiping out any saving and often ending up ahead on calories.

So the halo works twice. First it makes you underestimate what is in front of you. Then it gives you permission to eat more around it. A yoghurt labelled low-fat can lead to a bigger portion and a topping, because it feels like a food you are allowed to be generous with. The label does not just bend your perception, it quietly raises your intake.

None of these claims is a lie, exactly. They are just narrow truths dressed up to imply something broader. Here is what each one actually promises, and what it does not.

You beat the halo with a habit, not with willpower. The habit is simple: treat the front of the pack as an advert and go straight to the evidence on the back.

1. Cover the front claim. Mentally ignore natural, low-fat, or high-protein entirely. It is there to sway you, so give it no weight until you have checked the facts.
2. Read the ingredients list. A short list of recognisable foods is a good sign. A long list with syrups, isolates, and additives tells you it is an ultra-processed product no matter what the front says.
3. Compare per 100g, not per portion. Brands shrink the stated serving to make the numbers look small. The per-100g column lets you compare products honestly.
4. Check sugar and fibre together. Many halo foods are low in one thing and high in another. A low-fat label often hides added sugar, so read the whole nutrition panel.

There is one more layer worth naming. Some products stack claims, natural and high-protein and gluten-free all at once, precisely because each extra badge deepens the glow. A wall of virtuous words is a signal to be more suspicious, not less. The more a pack insists it is good for you, the more it is worth turning over and reading what is actually inside.

Do this a few times with the products you buy most and it becomes automatic. You stop seeing the friendly words and start seeing the food. That is the whole skill: not distrust of every label, just a habit of checking the claim against the ingredients before you let it change how much you eat.