How To Help Underweight Kids Gain Weight

Your skinny or underweight child may not be eating enough or having thyroid problems. Here are some expert inputs about healthy food and nutrition to help your child gain weight and stay healthy.

By Aruna Raghuram  • 13 min read

How To Help Underweight Kids Gain Weight

While overweight children may be the focus of health experts and the media, some parents find themselves with the opposite problem – underweight children.

Parents should be concerned as skinny kids face an increased risk of malnutrition, stunted growth and a weakened immune system.

How can I tell if my child is underweight?

How would you know if your child’s skinny physique is a part of his normal growth spurt or is he really underweight?

This is what Dr Uma Asopa, a paediatrician from Ahmedabad has to say,

“When the weight of your child drops below the fifth percentile of the expected weight for his/her age, he/she is underweight or too skinny. But watch your child. If he is happy, healthy, playful, active and eating reasonably well, he is probably doing fine,” says Dr Uma Asopa, a paediatrician from Ahmedabad.

A child may be skinny despite eating well. Or he may not be eating well because of poor appetite or because he is a fussy eater. In the first case, Dr Asopa advises parents to keep in mind the family history – whether they went through skinny phases – as some children have the genetic propensity to be skinny even though they eat normally. This is called ‘constitutional skinniness’ and has to do with the ability to burn more calories, she explains.

While causes of poor appetite need to be investigated, a picky eater should be handled with finesse!

How can I help my child gain weight?

Children keep gaining weight as they grow older. However, in some children, the weight gain may not be proportional to age. If this is the issue with your child as well, then here are a few tips to help you:

  • Have regular mealtimes, do not pressurise your child to eat, and keep mealtimes free of distractions
  • Include dairy products like cheese, cream and yogurt in your child's diet
  • Make fruits, beans, pulses and eggs a part of his regular diet
  • Increase portion size. If this is not possible, provide 6 to 8 smaller meals/snacks per day
  • Ask your child to avoid drinking excess water during meals. Instead, he should take a sip or two only
  • Encourage physical activity to stimulate appetite, and develop strong bones and muscles

What are some reasons my child is not gaining enough weight?

Poor weight gain in some children can be concern. Here are a few reasons why a child may not be gaining weight:

  • Inadequate intake of calories
  • Neurological issues
  • Improper digestion
  • Overactive thyroid gland
  • Bowel problems
  • Heart and kidney disorder
  • Genetic issues

When to worry about your skinny kid

Ryan Fernando, chief nutritionist and CEO of Bengaluru-based Qua Nutrition says: “The body mass index (BMI) is a good indicator of whether a child is too skinny. If a child has a BMI of less than 17, parents should be concerned.”

According to Ryan, tests for haemoglobin, Vitamin D and the albumin/globulin ratio will indicate what action needs to be taken. If a parent does not like the idea of invasive blood tests for her child, she should look for warning signs. For instance, white patches on the face are signs of low immunity, a bloated stomach is a sign of malnutrition, cracking nails and frequent coughs and colds are other signs that the child is not healthy. 

"Also, if a skinny child is not sleeping well, if his bowel movements are not regular or if he is not able to concentrate on studies, then there can be a problem," adds Ryan.

Dr Shirish Parikh, a paediatrician and nutritionist from Ahmedabad, feels that school absence is an important parameter to consider. 

“If a child is chronically ill, is frequently absent from school and has to be taken to the doctor often, the problem needs to be investigated. Severe loss of appetite is also a warning sign. Again, the personal and social behaviour of a child needs to be watched. If he is depressed, unenthusiastic or irritable, it can be a sign of ill-health. If a child does not play and does not take part in activities around him, it is a cause for concern,” adds Dr Shirish.

Also, parents need to be watchful of their child's growth. If a child has lost weight or has shot up in height without gaining weight, a paediatrician should be consulted. According to the National Institute of Nutrition (NIN), during the pre-adolescent period, a child grows, on average, 6 –7cm in height and 1.5–3kg in weight every year. Sudden loss in weight should also be checked out.

Dr Asopa suggests certain investigations to check for an underlying medical cause in underweight children. “You should rule out hormonal disturbances or deficiencies, food allergies, heart disease and digestion problems like malabsorption of nutrients. If your thin child frequently suffers from diarrhoea, nausea or vomiting, you should take note,” she says.

Weight gain diet plan for underweight child

Diet plan for an underweight child must include protein-rich foods such as milk, yogurt, cheese, eggs and soy products. This will help your skinny toddler or adolescent gain weight and muscle mass. Carbohydrates should make up the majority of your child’s diet, or 45-65 per cent of his calorie intake. Whole grain cereals, dry fruits (for snacks) are good foods for an underweight child. Smoothies made with yogurt, milk and fresh or frozen fruit are a treat and a great source of extra healthy energy.

But avoid feeding your child junk food or fatty food thinking that it won’t affect him because he is super skinny. 

Says dietitian and nutritionist Liza Shah, “Some parents stuff their thin children with food that contains more ghee, butter, cheese and oil, and make them drink full-fat milk in an attempt to get them to put on weight. Growing kids need more protein, fruits, vegetables and fibre. A child will not eat enough of the right kind of foods if his tummy is filled with the fatty foods.”

She insists that parents should give their children a variety of foods instead of just ‘roti, sabzi and dal’ meals. Children should be given the opportunity to choose. 

“Some healthy foods that can tempt your child are mithi roti made of besan and jaggery, boiled potato dishes, idlis, boiled chana salad and burgers made with wheat bread,” she says.
“If you want your child to gain weight, see that he eats frequently – at least three meals and two snacks a day – and give him calorie-dense foods,” advises Ryan.

For skinny children, his favourite suggestions are rice, potato, sweet potato, eggs and milk. French fries and pakodas are a no-no. Milkshakes, soups and smoothies can be given. Download colourful recipes and videos on food and show them to your child. Expand your horizons beyond the limits set by culture. For instance, if your child has taken a liking to pizza, experiment by making a healthy version for him.

Also, children may not eat well because of medical, climatic (we tend to eat less when the weather is hot) or psychological reasons. In some cases where the family environment at the dinner table is not good, children do not eat well. Parents should make mealtimes enjoyable and unrushed, and offer a variety of nutritious foods


Going to a nutritionist

Hemant Bhatt, father of an underweight child says, "My wife and I were very worried about our 10-year-old son Aditya who was underweight, he would get tired and irritable by early evening. My son’s appetite was very poor. He would eat a little of whatever food we gave him, and then say that he was not hungry anymore. We consulted a couple of paediatricians who suggested deworming and prescribed some vitamins. But the problem was not solved. Finally, we went to a nutritionist, Liza Shah. She explained to my son the importance of different groups of foods. My son was in the habit of eating dry snacks. She explained to him that nutrition comes before taste, and asked him to eat more vegetables and fruits of his liking. This worked. He put on one-and-a-half kg in one month."

Getting your child to eat healthy nutritious food

Delhi-based clinical nutritionist and dietitian Dr Ishi Khosla gives tips for parents:

  • Be a role model: If you eat healthy your children will do the same.
  • Stock smart: Keep only the right kind of foods like nuts, fresh fruits and vegetables and low-fat snacks in the house.
  • Involve kids in planning the daily menu and encourage them to help in cooking and shopping for nutritious food.
  • When you eat out, look for healthy options.
  • Permit junk food occasionally, but ensure that your child also gets the right amount of vegetables and fruits.
  • Educate your child about nutrition and good health.
  • Give your child water, not sugary drinks. Restrict other fluid intakes to one cup of juice and two cups of milk a day.
  • Slip in some healthy foods during snack time, not just empty calories.
  • Curb your child’s habit of watching television while eating – he may eat too much or too little because his focus is not on his stomach!

Managing fussy eaters

Lead by example by not being a fussy eater. Allow your child to choose, instead of forcing him to eat a particular food. A child likes to choose food from the age of two. If your child does not like lady’s finger or bottle gourd, find a healthy alternative. There are at least 15 other vegetables he can have. Once, I recommended a date milkshake to an underweight kid. The child immediately asked me whether he could have a strawberry and pista milkshake instead. When I agreed, the child was happy that he had been listened to, and his preferences were accepted.

About the expert:

Reviewed by Ryan Fernando on 18 September 2019. 

Ryan Fernando is an award-winning celebrity sports nutrition coach who is also the co-founder & CEO of India's largest chain of nutrition clinics.

About the author:

Written by Aruna Raghuram on 7 November 2016. Last updated on 5 May 2020.

Aruna Raghuram is a journalist and has worked with various newspapers, writing and editing, for two decades. She has also worked for six years with a consumer rights NGO. Presently, she is a consultant with ParentCircle.

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