What should you know about junk food and obesity?

Junk food can contribute to obesity when frequent portions provide more energy than the body uses, especially when meals are low in fibre and filling nutrients. Foods such as sugary drinks, fried items, sweets and refined snack products can be easy to eat quickly and may not keep you satisfied for long. Weight is also shaped by sleep, activity, medicines, stress, health conditions, genes and access to nourishing food, so it is not a matter of willpower alone.

A pattern of frequent high-energy food and drink can make it harder to maintain a healthy weight. Large portions, eating while distracted and liquid calories may add energy without producing much fullness. Over time, obesity can increase the chance of problems such as hypertension, prediabetes, type 2 diabetes, acid reflux, gallstones, gout and obstructive sleep apnoea. These conditions do not affect everyone with obesity, and eating one snack or meal does not cause obesity by itself.

Start with a change that fits your routine. Replace sugary drinks with water or an unsweetened option, add vegetables or fruit to meals, and choose beans, eggs, fish, poultry or other protein foods alongside whole grains where possible. Serve food onto a plate rather than eating from a packet, slow down enough to notice fullness, and keep highly tempting snacks less accessible. Regular walking or another activity you can sustain may support health even when weight changes slowly. A doctor or dietitian can help identify medicines or medical conditions that affect weight and create a realistic plan.

Arrange a medical review if weight is rising steadily, daily activities are becoming difficult, or you have loud snoring, witnessed pauses in breathing, persistent heartburn, marked thirst, frequent urination or painful swollen joints. Seek urgent help for severe chest pain, severe breathlessness, fainting, sudden weakness or confusion. A clinician may check blood pressure, blood glucose and other health risks, while discussing support that does not rely on blame.

You could ask: Could a medicine or health condition be affecting my weight? Which checks are appropriate for me? What eating or activity change would be safest to start with? Would a dietitian, structured weight-management programme or other treatment be suitable?