If your child suddenly starts picking at meals during a spell of hot weather, it can be unsettling. But a smaller appetite for a few days can be a normal response to heat, particularly if your child is drinking well, has their usual energy and seems otherwise healthy.
Author
- Rachel Woods
Associate Professor of Medical Education, University of Nottingham; University of Lincoln
Research directly examining heat and appetite in children is limited. Studies in adults, together with experimental research into the biology of appetite, suggest that warmer conditions can reduce food intake and affect some of the brain systems involved in controlling hunger.
So there are several reasons why dinner may suddenly lose its appeal when temperatures climb.
Eating produces heat
Eating takes energy. After a meal, the body has to digest food, absorb its nutrients and process or store them. The resulting increase in energy expenditure is known as the thermic effect of food .
This process also produces heat. In warm conditions, when the body is already working to prevent its core temperature rising, this additional heat production may be one reason we feel less inclined to eat. Experimental studies in adults have found lower food intake in warmer environments , although the size of the effect varies and we cannot assume children respond in exactly the same way.
There may also be a connection within the brain itself. Research into the neural control of eating suggests that some of the circuits involved in sensing temperature are linked with those controlling appetite. Scientists are still working out exactly how this happens.
The body is busy keeping cool
When we become hot, blood flow to the skin increases , helping the body transfer heat to its surroundings. Sweating provides another important cooling mechanism.
This does not mean a healthy child's digestive system stops working in hot weather. But it does mean the body is making significant physiological adjustments to cope with the heat.
There is no particular reason, therefore, to insist on a large cooked dinner if it has suddenly become unappealing. The same foods and nutrients can often be offered in a form that feels easier to eat.
Drinks can affect appetite too
Children need regular access to fluids in hot weather. Babies and young children are particularly vulnerable to dehydration, so maintaining fluid intake becomes especially important when temperatures rise. The NHS advises offering children plenty of fluids during hot weather .
What they drink can also affect how much they want to eat. Milk, juice and sugary drinks contain energy, and children vary considerably in how well they adjust what they subsequently eat after consuming calories in drinks. In one study of children aged four to seven, children ate less at lunch after a higher-energy drink, but there was considerable variation between individual children .
There is no need to restrict water because you are worried it will spoil their dinner. Keep it readily available. But repeatedly offering calorific drinks between meals can change the amount a child wants to eat later.
Children do not eat the same amount at every meal
Parents tend to notice the meal their child has barely touched. Children often regulate their food intake over a longer period.
Research into children's eating behaviour has found that the amount young children eat at individual meals can be remarkably variable , while their overall energy intake is better regulated over time.
So a child who eats very little at lunchtime may be ravenous later. Another may simply eat less that day. A few days of smaller meals during very hot weather are unlikely to cause concern in an otherwise healthy child who is drinking adequately and remains active and well.
Change the meal rather than turning it into a battle
Hot weather is a good time to loosen expectations about what a "proper dinner" has to look like.
A picnic-style meal might include sandwiches or pitta, hummus, cheese, yoghurt, fruit and raw vegetables. Smaller portions can be offered initially, with more available if the child wants it.
Parents can provide a varied selection of regular meals and snacks while allowing the child to decide whether to eat and how much. Research on responsive feeding generally supports responding to children's hunger and fullness cues, while pressure to eat has been associated with greater food fussiness and less enjoyment of food.
If dinner consists of half a yoghurt, some fruit and a piece of toast one evening, there is little benefit in negotiating another six mouthfuls. Keep offering ordinary nutritious foods and consider what your child eats across several meals rather than expecting every plate to be perfectly balanced.
When should you be concerned?
Loss of appetite deserves more attention when a child also seems unwell.
Seek medical advice if your child is refusing fluids, repeatedly vomiting and unable to keep fluids down, becoming unusually drowsy, or showing signs of dehydration such as peeing much less than usual, having a dry mouth or producing few or no tears when crying.
A very high temperature accompanied by confusion, fast breathing, a seizure or loss of consciousness can indicate heatstroke, which is a medical emergency .
It is also sensible to speak to a healthcare professional if a child's poor appetite continues after the hot weather has passed, particularly if they are losing weight or there has been a broader change in their health.
For most otherwise healthy children, though, eating less during a hot spell is temporary. Keep drinks available, continue offering nutritious food without pressure, and allow appetite to increase again when temperatures fall.
Rachel Woods does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
