If you are confident that you do not suffer from any of the underlying conditions that can cause underweight or excessive weight loss and if you already eat a considerable quantity of healthy foods, but still either lose weight or fail to gain any, you need to add high-energy snacks or liquid meal supplements to your daily food intake.
How to add 2100 kJ or 500 cal to your diet
Each of the following snacks will add 2100 kJ or 500 cal to your existing diet:
8 biscuits or crackers with 30 g cheese and 1 cup of ice cream
1 glass (300 ml) of Milo or Ovaltine or Nesquick made with full-cream milk plus 2 t of sugar, with 2 biscuits
1 cup (250 ml) of fruit juice with 40 g of peanuts and 40 g of raisins or other dried fruit
2 Energy bars and 1 cup (250 ml) of full-cream milk
Avocado smoothie (see Part II for recipe), using 1 cup (250 ml) of full-cream milk, 1 ripe mashed avocado (145 g), 2 t of honey, and adding 30 g of full-cream milk powder
Fruit smoothie (see Part II for recipe), using 1 cup (250 ml) of full-cream milk, 2 ripe mashed bananas, 2 t of sugar, and adding 30 g of full-cream milk powder
2 slices (60 g) of wholewheat or seed bread with 1T (15 g) polyunsaturated margarine and 2 T (30 g) of peanut butter or cream cheese, and 2 t (10 g) of jam or syrup
1 slice of cheese or chocolate cake with 200 ml full-cream milk
If you have three of these snacks between meals every day, you will be adding 6300 kJ (1500 cal) of energy to your diet which should produce a weight gain of 1 kg per week.
Using liquid meal supplements
There are many different liquid meal supplements on the market which you can buy at most chemist shops or gyms.
Let's look at two examples, namely Fresubin Energy-Fibre, and Nestle Nutren with Fibre:
Fresubin Energy-Fibre contains 630 kJ or 150 cal per 100 ml, so if you drink 200 ml (1260 kJ or 300 cal) three times a day between meals, you will increase your daily energy intake by 3780 kJ or 900 cal a day. Using 3 x 200 ml of this liquid meal supplement a day will produce a weight gain of 1 kg every 10 days.
Nestle Nutren with Fibre provides 420 kJ or 100 cal per 100 ml, so if you have 200 ml (840 kJ or 200 cal) three times a day between meals, your daily energy intake will increase by 2520 kJ or 800 cal a day. Using this product you should gain 1 kg every 2 weeks.
It is vital that you increase your energy intake (with snacks or liquid meal intakes) slowly and gradually. It is counterproductive to suddenly eat three high-energy snacks or drink 3 x 200 ml of a liquid meal supplement per day.
You may feel too full, bloated or even nauseous because your stomach and metabolism are not used to such a lot of food. Such symptoms can be most discouraging and put you off trying to gain weight.
Start off by adding one snack, or 1 x 200 ml of liquid meal supplement, to your daily intake, while keeping your other food intake constant.
When you feel completely happy and confident that you are handling the one snack or one liquid meal a day, add another snack, or another 200 ml of liquid meal supplement to your intake.
Give your body time to get used to this addition and once you are settled, add the third snack or the third 200 ml of liquid meal supplement to your diet.
By being careful and sensible when you add additional food to your daily intake you will ensure that you don't fail in your attempt to gain weight.
Consult a dietician
If you struggle to stick to a high-energy diet, or if you cannot boost your energy intake with additional snacks or liquid meal supplements as outlined above, you need to consult a clinical dietician (ask your GP to refer you or look in the Yellow Pages under "Dieticians"). He or she will guide you through the process of increasing your daily energy intake.
Other things you can do
Conserve energy by relaxing as much as possible and sleeping at least eight hours a night if you can.
Take a vitamin B complex supplement to stimulate your appetite (buy at your chemist).
Do some gentle, relaxing exercise, such as yoga, to defuse your overactivity if you tend to be on the go all day – something that can burn up too much energy and cause underweight.
Hopefully those Readers who are battling to gain weight, will be able to apply the advice given in this series on Undernutrition Parts I, II and III, so that they can gain weight steadily. – (Dr Ingrid van Heerden, DietDoc)
(Krause's Food, Nutrition & Diet Therapy, 10th Ed. WB Saunders Co, USA)
Any questions? Ask DietDoc.