Body size and health

A healthy body size is different for everyone. Your healthcare provider may use your body mass index (BMI), which uses body weight and height, along with other measures (eg, the size of your waist circumference) to work out whether you're in the healthy weight range for your gender, height and ethnicity. It's important to note, BMI isn't a perfect measure of a healthy weight as it doesn't account for lean muscle mass. Body composition (the amount of muscle and fat you have) and where the fat is on your body can be more important in determining health.

The size of your waist is an indicator of risk for certain health conditions.

• A waist circumference of more than 80 cm in women and more than 94 cm in men is associated with an increased risk of type 2 diabetes, hypertension (high blood pressure) and cardiovascular disease.
• A waist circumference of more than 88 cm in women and more than 102 cm in men greatly increases this risk.

Many people feel uncomfortable being weighed. When you see your General Practitioner (GP), specialist or other healthcare provider, it's okay to say no to being weighed. If your healthcare provider insists, ask them if it's medically relevant. Sometimes they need to know your weight to help manage a medical condition or to work out how much medicine you need. You can ask to not know what your weight is.

In some cases, losing weight may reduce your risk of some health conditions. Even a small amount of weight loss (5 to 10% of your total body weight) may produce health benefits. These include improvements in blood pressure, blood cholesterol and blood glucose. If you've been diagnosed with prediabetes, even small amounts of weight loss may stop this from progressing to type 2 diabetes. With polycystic ovarian syndrome (PCOS) and infertility, modest weight loss (beginning at 2 to 5% of your body weight) may bring improvements in menstrual irregularities and fertility. However, just because these illnesses can occur in people with a high body mass index (BMI) doesn't mean body size is the cause.

Body size is just one of the ways you and your healthcare provider can check on your health. Other ways include blood tests, measuring blood pressure, looking at body composition (how much muscle and fat you have) and looking at eating and exercise behaviours. The Te Whare Tapa Whā model of health(external link) represents a whare/house with 4 equal sides representing our spiritual (taha wairua), physical (taha tinana), family (taha whānau) and mental health (taha hinengaro). If one of the sides isn’t sturdy, the whole whare will be shaky, so while it’s easy to focus on one aspect of your health (eg, your diet), it’s actually important to look after yourself in all areas. 

Read more about Te Whare Tapa Whā and wellbeing and Māori health(external link) and Pacific health(external link). 

There are times in life when it's healthy and normal to gain weight, eg, during pregnancy and menopause. When recovering from illness or certain medical conditions, it can be normal and healthy to gain or regain weight, eg, people newly diagnosed with coeliac disease often gain weight when they begin treatment.

There are times when weight loss isn't advisable, for example when you're diagnosed with a serious illness, such as cancer or kidney failure, or if you have an eating disorder. If you're losing weight and you're not sure why, talk to your healthcare provider or specialist. Read more about how to put on weight.

Health behaviours can improve metabolic factors without necessarily needing to lose weight. There are 6 behaviours that are important for everyone to promote health and well-being, regardless of body size:

• Eating more fruit and vegetables
• Regularly moving your body
• Improving rest and sleep
• Managing stress
• Not smoking
• Not drinking too much alcohol.

Taking part in group programmes or support can make healthy behaviours more enjoyable and sustainable. Seek out other people who are making changes. Ask your healthcare provider for self-management support information or about available programmes, eg Green Prescriptions. 

The reasons for your body size are not as simple as energy in, energy out.

There are many factors that influence body size:

• Medical conditions.
• Medicines.
• Income.
• Genetics.
• Age.
• Ethnicity.
• Social factors that are out of your control, eg, being surrounded by high energy or calorie dense food choices and larger portion sizes.
• Healthy food can be costly and can take time to buy and prepare, which can be difficult with modern lifestyles.
• Physical activity can also cost money and take up time, which can be difficult, especially for parents and caregivers.
• Living in some communities may mean it's harder to find or afford healthy food and access free physical activities. 

When faced with challenges, be kind to yourself and start back when you're ready. Small changes that you can stick with over the longer term will make the most difference. Keep adding small changes and you will be on your way to caring for your body and mind.

Image credit: Canva

Size diversity is when people are genetically designed to have different sized bodies. People can be many different sizes and still be healthy.

Weight stigma and bias are negative attitudes and stereotypes associated with body weight. Weight discrimination is when a person is treated in a negative way because of the size of their body. People who experience weight stigma have higher stress, poorer health outcomes and are less likely to seek medical attention.

Many people experience weight-based discrimination within the medical system. If you're denied medical treatment because of the size of your body, ask your healthcare team what treatment they would offer you if you had a smaller body size. You can take a support person to your healthcare appointments, and you can seek a second opinion.

If weight stigma is affecting your mental health, remember that many factors contribute to body size. Many people struggle with weight management. Weight re-gain is common. Even a small amount of weight loss (5% to 10%) can improve health outcomes. Health can improve without weight loss when you're engaging in healthy behaviours, eg, healthy eating and physical activity. Reach out to a trusted healthcare provider, whānau and community for support if you have any concerns about your mental wellbeing. Just a Thought and Beating the Blues(external link) both offer free online courses. 

If you're concerned about your weight, talk to your whānau, peers or healthcare provider. Weight is one part of a very big picture. Work with your healthcare team, you can ask for a blood test and get your blood pressure tested too. This will help give your healthcare provider an idea of your health status.

It's important to make small changes that fit your life. Weight management is easier in a group, knowing you're not alone and having that extra support when faced with challenges. Look for community-based programmes in your area, eg, Green Prescription. You can also see a dietitian or registered nutritionist, who is trained in nutrition. They can help work out an approach to improving healthy eating that suits your culture and lifestyle. Doing it as a family is a good way to support each other. Find a dietitian(external link).