In our society, where there is a large number of overweight and obese people, there is much more emphasis on losing weight rather than gaining weight.
People find it hard to accept that thinness (unrelated to anorexia nervosa) is unhealthy. However, it has been shown that people at or above average weight at age 50 live longer than those who are underweight.
What is underweight?
The most widely accepted method to assess weight is body mass index (BMI). It determines whether your weight is putting you at risk and is based on your height and weight. The normal weight BMI range is 18.5 to 24.9. Underweight is a BMI less than 18.5.
Be aware that BMI guides can be misleading - BMI tends to relate to fat mass on the body but, for active or more muscular people, BMI may overestimate this. Plus, people of Asian origin tend to carry a higher fat mass for a given BMI, and those of Polynesian origin have a proportionately lower fat mass for a given BMI.
Being mildly underweight (BMI of 18) doesn’t necessarily mean serious health problems, but people who are very thin lack energy reserves, are prone to getting infections and feel the cold because they don’t have a layer of fat to keep them warm.
If you have lost weight and don't know why, you should see a doctor in case you have an underlying health problem. Chances are though if you have been mildly underweight all your life and both parents are too, there’s no illness at the root of your problem.
For most people, being underweight means poor nutrition – insufficient kilojoules eaten on a regular basis.
Possible causes of lost weight
- chronic illness such as renal disease
- alzheimers and dementia
- chronic pain
- social isolation
- an elderly person who is housebound
- swallowing disorders
- chronic dieting.
How to gain weight
To gain weight you must eat more kilojoules every day from a range of healthy foods. Regular exercise is important to help build muscles so that weight gain is not just fat. To gain 1kg of weight in a month requires 1000 extra kilojoules a day.
A plan to increase weight should focus on:
- Increasing your food intake – try eating larger portions.
- Relaxing the rules on how much fat you eat. Fat contains more than twice the kilojoules as protein and carbohydrates so increasing your fat intake can rapidly make a difference to weight gain. Add some healthy oils (e.g. olive oil, canola oil) to your meals.
- Including energy dense foods throughout your daily meals, eg, peanut butter or cheese on toast instead of marmite, milkshake instead of low fat milk, ice cream on fruit, avocado instead of cucumber, juice and milk instead of tea and coffee, Complan or Sustagen drink.
- Avoiding too many bulky low energy foods. Raw vegetables and fruit are nutritious but you fill up quickly well before you have eaten enough kilojoules.
- Trying to eat 5-6 smaller meals as this may be easier if bigger portions are difficult to eat.
If you have lost weight due to an illness you may benefit from a liquid nutritional supplement. Dietitians and doctors can recommend these.
Tips to increase kilojoules
- Eat cereals with added fruits and nuts.
- Make porridge with milk instead of water.
- Add jam, cheese, avocado and plenty of margarine spread to toast.
- Eat cream and ‘mealy’ soups instead of clear soup. Make with milk and top with cheese or croutons.
- Snack on dried fruit
- Add nuts on to cereals and baking.
- Raw vegetables and salads are low in kilojoules but you can add avocado, nuts, sunflower seeds or raisins.
- Choose desserts that are nutritious as well as high in kilojoules, e.g. milk puddings, steamed fruit puddings, custard, ice cream.
Many underweight people can feel uncomfortably full when they start eating larger portions more frequently to gain weight. This feeling does go away eventually, but it does take some perseverance. A major barrier to underweight people gaining weight is their unwillingness to eat more food. Increasing your kilojoule intake is necessary to increase your weight.
Make a tasty drink for one!
|Chocolate milkshake||Mango smoothie||Sustagen|
|250ml milk 2 Tbsp yoghurt 1 Tbsp skim milk powder 2 Tbsp chocolate toppingPlace ingredients into a food processor or blender and process until thick and frothy. Pour into a glass and serve immediately. Kilojoules/serve: 1160||250ml milk 1 Tbsp skim milk powder 1 Tbsp honey 4 ice cubes ½ mango, stoned, peeled and chopped. Place ingredients into a blender or food processor and process until smooth. Pour Into a glass and serve immediately. Kilojoules/serve: 1315||Mix 60g, 3 level Tbsp of Sustagen powder with 200ml milk. Pour into a glass. Kilojoules/serve: 1370|
Tbsp = tablespoon
|Breakfast||Morning tea||Lunch||Afternoon tea||Dinner||Supper|