Practices

Most claims about food and behaviour rest on weak studies. The ones worth taking seriously give each person both the real thing and a dummy at different times, with nobody knowing which is which, so that hope and expectation cannot do the work.

The food colouring trials are the standard example. Around 150 children each received drinks containing a preservative plus one of two dye mixes, or…

The same brand of sweets is often made with plant based colours in one country and artificial ones in another. If a company can make it without the dyes elsewhere, the dyes are not essential to the food.

Nine artificial colours are approved in the US, and the volume approved for use rose roughly fivefold between 1950 and 2012. One of them, Red No. 3,…

Skin prick and IgE blood tests find real allergies. The IgG food sensitivity panels sold direct to families have not been shown to measure sensitivity at all, and they tend to come back with a long list of foods to avoid.

IgG antibodies mostly show that you have eaten something, not that it harms you, which is why the results look alarming and change so little when…

A real food allergy shows itself on the body: a rash, a swollen or inflamed throat, something you can see. Behaviour on its own does not identify one, although behaviour often improves once a genuine allergy is dealt with.

One child's attention and mood went back to her usual level once berries came out of her diet, and what made that findable was the rash and the sore…

The studies linking pesticide levels to ADHD are tangled up with income, since families least able to buy organic differ in plenty of other ways too. If organic food is affordable for you, fine. If it is not, you are not failing your child.

In one study of 1,140 children, 94% had detectable pesticide in their urine, and ADHD was about twice as common among those with higher…

Most eating advice quietly assumes a budget. Fresh food is expensive and does not keep, so a household relying on food assistance ends up buying what lasts, and what lasts comes in tins and packets.

If money is the constraint, say it out loud rather than nodding along and then failing quietly at home. The advice can be rebuilt around what is…

Put an actual number on it: how many coffees, teas, energy drinks and colas in a normal day. Without that number, your sleep problems, your anxiety and how well a medication is working are all being read against an unknown.

People underestimate this, partly because it feels embarrassing and partly because a large takeaway cup is often two or three servings. Count across…

Stimulants sharpen focus in almost anyone, so responding well to one does not confirm you have ADHD. The diagnosis comes from your history and how you function, not from a trial of tablets.

This cuts both ways. Someone can be handed a diagnosis on the strength of a good response, and someone else can be doubted because their response was…

Health advice usually assumes a kitchen, a fridge and money for the week. If you are working with less than that, the answer is not to try harder at the advice. It is to shrink the plan until it fits what you actually have.

A plan you cannot keep does more than fail. It quietly adds to the pile of evidence that nothing you do makes any difference, and that pile is heavy…

Saying a difficulty is in the past is not the same as saying it was never real. Sometimes a picture changes because something that was making it worse got taken away, and the honest words for that are neither cured nor imagining it.

People who have been disbelieved by doctors are very sensitive to this, and with reason. The choice usually gets offered as either it was all in your…