Is my child underweight?

These days we mostly hear about obesity in children but an underweight child can also be a cause for concern. So what is underweight? The old saying, ‘You can’t fatten a thoroughbred’ may apply to children who are naturally slight, who have slim parents and who are on the lower end of the growth charts and have consistently been so. But how do you know if there is a problem?

Growth and development remain one of the most important indicators of your child’s health. Some children between 6 and 18 months will shift percentiles, but usually by 24 months this has settled and their growth is consistent. The children who slide down the growth charts are of concern, particularly those 24 months+ who may have moved down two major percentiles i.e. from the 80th to the 40th and continue in this fashion. Also, if a child passes the lower percentiles (of about the 5th but depending on who you talk to it can be as low as the 3rd) then intervention should be sought.

If you are concerned or have noticed that your child isn’t growing at their usual rate, your first port of call is your GP or early childhood nurse. They can assess your little one, check him/her over, review their eating and health, and support you both.

Even after having had all the checks done as to why their child is light, parents may still be mystified about how to help them gain some weight. It is important to keep in mind that increasing the body weight of a child isn’t always an easy task; children have very high energy demands and small capacity in their stomachs so simply meeting their daily energy needs can be tricky, let alone trying to exceed them so that they gain some weight.

Why is my child underweight?

In most instances it is likely to be a case of genetics; that their genetically predetermined weight and height is as it is.

Other factors:

  • A child can be very active and therefore require a lot of energy input (calories) just to meet their daily needs.
  • Eating issues such as fussy eating which is a stage or food neophobia (fear of new foods) which is often more personality driven.
  • Underlying nutrient deficiencies such as iron can affect eating habits.
  • Some children are over-reliant on nutrient-dense fluids such as juice or milk. The former can cause toddler diarrhoea and both can displace food and meals as well as create nutrient imbalances.
  • Possible learned dislike of food and/or healthy eating habits.
  • Sometimes we can become overbearing with food and put children off.
  • Pure disinterest in food can be due to distractions or just general busyness.
  • Food allergies and restricted diets can lead to difficulties.
  • Short and protracted illnesses.
  • Undiagnosed illnesses.
  • Oral mechanical issues, such as muscle development, enlarged tonsils and being tongue-tied.

So what should I do?

In some cases there may be nothing you can do. You may well be offering a wide variety of healthy foods, your child drinks only water, is healthy and growing at a steady rate despite not weighing what we believe is ideal.

But if you think some of the issues above might be at play, following are a few suggestions that may be useful. Most often the trick to weight gain in young children (healthy weight gain) is protein and in older children it can be induced by a combination of diet and exercise.

Check the protein and energy from fat

Initially concentrate on diet by ensuring regular protein foods and a little more fat (ideally healthy fat from whole foods). But don’t run for the kitchen scales, you don’t really need to measure out grams of protein. An easy rule of thumb is to use your little one’s palm as a guide; roughly their palm (length and width) is enough protein for each meal. Try to include at least a little protein in snacks also.

Protein-rich foods include:

  • Meat (red meat, pork, chicken, turkey etc.)
  • Fish
  • Dairy (milk, cheese, yoghurt, ice-cream etc.)
  • Eggs
  • Nuts, seeds, beans, legumes – linseeds, pumpkin seeds, sunflower seeds, almonds, soy, sprouts and so on
  • Breads and cereals
  • Seaweed

Some snack and meal ideas

  • Offer your child’s main meal when they are hungriest, so if you find your little one eats best at lunch then offer a substantial dinner-type meal.
  • Offer milk drinks after meals and snacks so your little one doesn’t fill up on fluid and lose interest in meals.
  • Avoid apple and pear juice as it can lead to toddler diarrhoea, which never helps weight gain.
  • Try offering milk in the form of a fruit and yoghurt smoothie (which is a great additional snack for weight gain because most kids love them). Your little one will get a range of nutrients, and you can also add other foods or supplements.
  • You can also add ground linseeds, pumpkin seeds, sunflower seeds and nuts (assuming no risk of allergy) to cereals, smoothies and so on.
  • Ensure that each meal, including snacks, has some protein. It can sometimes be tricky to achieve this with snacks so think about toppings on crackers such as cream cheese, almond paste, avocado, cheddar cheese, hummus, tahini, tuna, salmon (which can be mixed with mayonnaise to form a paste), meat slices, yoghurt with fruit, cheese with crackers, healthy snack bars with dried fruit and so on.
  • Consider eggs a few times a week: scrambled eggs, whole boiled egg, omelette, boiled egg mashed with mayonnaise, shredded egg flip with rice and so on.
  • Add some cheese and a little butter to mashed vegetables, soups and baking (such as scones).
  • Use more cheese sauces in meals and pasta dishes.
  • Mayonnaise can make a great dip for fish fingers, spring rolls, fish cakes, falafel as well as a salad dressing or added to mashed foods.
  • Milk-based puddings made with rice, sago, tapioca, bread and so on.
  • Avoid sugary and junk foods such as biscuits, lollies and chips before meals or snacks which can simply fill up your little one with foods that do little to help gain weight healthily.
  • Keep portions small so as not to overwhelm with a big meal at the end of the day, plus finishing off a plate is a good motivator for you both.
  • Offer food regularly over the day, for example three meals and three snacks a day, one being a nice healthy supper at night after dinner.
  • Make food fun and interesting: try novel straws, decorative meals, even having a picnic in the lounge can be a nice change.
  • Limit distractions such as toys and TV and always use positive words; avoid stress (for both of you) during meal-times.

Next step

If you find that diet alone just isn’t enough – as can be the case if your little one has very strong views on what passes as enjoyable food – you may need to consider a supplement. Medical professionals use a high-calorie powders. Ask for information from your pharmacist, GP, paediatrician or dietician.

Quality children’s protein powders are also excellent. One specifically made for children is Kids MetaMeal by Metagenics. You need to see a professional for such supplements (manufacturers’ websites may be helpful). This is a healthy way to gain bulk as it avoids excessive intake of simple sugars and saturated fat, neither of which assist long-term weight gain or health.

You may read that your child should eat high-fat, low-fibre foods such as white breads and fatty meats, for example salami. The theory with low-fibre is that it avoids overfilling on complex carbohydrates, and the idea around eating fat is to increase calorie intake. It may sound good in theory but can go against some dietary guidelines for health and may interfere with the variety of nutrients in the diet. Always focus on quality whole foods. Increasing fat is fine, a little extra fat won’t go astray, especially as we now know that saturated fat isn’t as bigger issue as we once thought, but keep the emphasis on healthy fats from foods such as avocado, fish, nuts and seeds, and opt for healthy wholegrain products. There is no point swapping one bad habit for another.

Remember, the aim is permanent weight gain, which is largely going to be achieved via increased body tissue such as muscle; hence, the focus should be on protein and a healthy diet. Body fat is actually quite light, and generally isn’t a long-term answer to healthy weight gain. Nutrients are important in order to make body tissue so a healthy diet is always the platform upon which you can then build other specific diets.

This tip sheet is not designed to replace medical advice. Always seek medical advice if your child is unwell. This sheet may be reproduced in whole with full acknowledgement of the source. Leanne Cooper from Cadence Health and Nutrition,