Factors that affect weight

Maintaining a healthy weight is important for good health and wellbeing. But overweight and obesity is a complex issue – many factors affect body weight, and people’s ability to maintain a healthy weight.

What affects weight

Excess weight generally results from an energy imbalance. This is where the energy taken in from eating and drinking is higher than the energy used through physical activity.

But overweight and obesity is a complex issue, influenced by many factors, including:

  • genetics
  • cultural background
  • medical conditions and disability
  • mental ill-health – which can affect appetite and motivation to shop and cook healthy food or be active
  • some medicines – which can increase appetite or slow the metabolism
  • eating disorders
  • drugs, tobacco or alcohol
  • where people live, go to school and work
  • the media
  • availability of convenience foods
  • portion sizes
  • time pressures – which can make it hard to cook healthy meals and exercise
  • lifestyle
  • shift work – due to disrupted sleep and eating patterns
  • inadequate sleep – people who sleep less than 6 hours a night are more likely to gain weight.

If you are concerned about your weight and think any of these factors apply to you, speak to your doctor.

Healthy weight for everyone

Eating healthy food and being physically active are important to achieving a healthy weight.

But many other factors come into play – if you’re worried about your weight, or having trouble maintaining a healthy weight, speak with your doctor.

Some groups in our community also face extra challenges in maintaining a healthy weight.

Aboriginal and Torres Strait Islander people

Overweight and obesity among Aboriginal and Torres Strait Islander people has been rising. In 2018–19:

  • more than 1 in 3 of those aged up to 17 were overweight or obese
  • 3 in 4 adults were overweight or obese.

Factors include:

  • a change in diet, from a more natural diet based on hunting and bush foods, to processed foods
  • being more likely to live in lower socioeconomic areas – which have higher rates of overweight and obesity
  • being more likely to live in regional or rural areas – where healthy foods are harder to find and more expensive.

People living in regional and rural areas

People living in regional and rural areas are more likely to be overweight or obese than those who live in cities.

When compared with cities, challenges in regional and rural areas include:

  • higher prices for healthy and fresh food
  • lower availability of fresh fruit and vegetables, and of healthier substitutes, such as wholegrain bread and reduced-fat milk
  • lower-quality drinking water, which might lead people to drink more sugary drinks
  • fewer indoor gyms, sporting grounds or team sports.

Cultural backgrounds

Cultural background can affect body weight and how people view it. Factors include:

  • genetic background – healthy body mass index (BMI) ranges vary for some cultural groups
  • a sudden change in diet for recent migrants to Australia, which can lead to weight gains
  • differing views of what healthy weight is – in some cultures, being overweight is a sign of health and wealth
  • differing priorities – for example, putting homework before physical activity for children.

People with disability

The challenges people with disability face depend on their ability, but include:

  • a reduced ability to be active
  • limited access to healthy food choices
  • dependence on family members or carers to provide meals
  • a medical condition or medications that affect appetite or metabolism
  • struggling to chew or swallow food.

Standard BMI and waist measurements might also not suit all body shapes.

Tackling the challenges

There are things you can do to eat healthily and be active.

  • Buy in-season fruit and vegetables from local suppliers, if available.
  • If you’re unsure about the water supply, boil water first, then keep it in the fridge.
  • If fresh fruit and vegetables are unavailable, buy frozen and canned ones instead. Read the labels to make sure they’re not high in sugar, salt or saturated fat.
  • When fresh fruit and vegetables are available, buy in bulk, cook, and freeze to eat later.
  • If you don’t have access to team sports or a gym, find exercises you can do at home, or get into the habit of going for a brisk walk every day.

Read what we’re doing to reduce overweight and obesity in Australia.

Last updated: 
29 July 2021

Help us improve health.gov.au

If you would like a response please use the enquiries form instead.