How to gain weight in a healthy way

As the Western world grapples with an obesity and metabolic health crisis, the media’s focus is often on losing weight to avoid ill health associated with high levels of body fat. 

However, many people have a similarly challenging goal that receives much less attention: Putting weight on to achieve a healthy weight.

In this article, we’ll explain how to know if you are underweight and any associated health risks. We also provide tips and advice on how to gain weight in a healthy way.

How can you tell if you are underweight?

Although BMI is an imperfect tool, it can still help gauge whether you are a healthy weight.

These are the BMI categories as outlined by the CDC:

• Underweight: less than 18.5

• Healthy weight: 18.5 to 25

• Overweight: 25 to 30

• Obese: 30 or higher

However, these categories vary by ethnic group. Try this online tool to find your BMI.

Energy needs vary depending on age, level of activity, and other factors. 

It’s also worth remembering that food quality is just as important as the energy you take in. To function properly, your body also needs fibre, protein, healthy fats, minerals, and vitamins.

Risks associated with underweight

The health risks associated with carrying excess body weight, and specifically excess body fat, are well-known, but being underweight also increases the risk of issues, including:

• eye problems

• tiredness

• depression

• reproductive issues

• inflammation

• poor wound healing

Being underweight might also be a sign that an individual is malnourished or living with an eating disorder.

Although eating disorders are rising in all age groups, overall, being underweight is most common in older adults, where it’s linked to:

• impaired muscle function

• decreased immune function

• reduced thinking skills

• sarcopenia (muscle loss)

• decreased bone health

What can cause underweight?

There are a number of reasons why someone might become underweight. As we mentioned above, aging and eating disorders are important factors, but others include:

• physical or mental illness

• very high levels of activity

• long term stress

• high metabolism

• family history of being underweight

• disordered eating

Next, we’ll provide six tips for gaining weight in a healthy way. 

How to gain weight in a healthy way

1. Honor your hunger cues

Many of us — for a wide range of reasons — sometimes ignore our hunger cues.

Perhaps we’re too busy or stressed; maybe we’re prioritizing feeding the kids rather than ourselves; or perhaps we’re so used to fad dieting that we automatically ignore the pangs when they arrive.

It’s important to remember that these cues are a sign that your body needs energy. So, when you feel hungry, make sure you eat something. 

2. Eat more regularly

If you find that you get full very quickly, try eating smaller meals more often — making sure you have access to nutritious snacks throughout the day can help achieve this.

And if you often forget to eat, set regular meal times every day and prioritize them in your day.

3. Exercise

Although many people exercise regularly to lose or maintain weight, it can also help you gain weight. 

However, prioritize rest and try to avoid exercising for long periods of time (like long runs, for example); instead, try short bursts of muscle-building exercise.

In particular, load-bearing exercises such as carrying weights and strength training at home or in the gym can help you build muscle mass.

This will increase your overall weight and help you achieve a healthy body composition.

You might also find that exercising naturally increases your appetite.

Good options include:

• Pilates.

• Gardening. 

• Bodyweight exercises, like squats during TV commercial breaks or while brushing your teeth.

• Carrying shopping in bags rather than taking a cart. 

• Dancing.

• Household chores like mopping, hoovering, and carrying laundry.

To ensure you have adequate protein to build extra muscle, make sure you consume healthy protein sources, such as:

• beans, like edamame, kidney, black, and pinto.

• lentils

• fish

• nuts

• tofu

• oats

• quinoa

• eggs 

4. Focus on energy-dense foods

Of all the macronutrients, fat contains the most energy — 9 calories per gram. In comparison, carbohydrates and protein contain around 4 calories per gram.

Some forms of fat, like saturated and trans fats, are associated with poorer health. However, mono- and polyunsaturated fats are an important part of a healthy diet. 

Cheese, eggs, and natural or Greek-style full-fat yogurt are also good options. They have relatively high amounts of energy per portion. 

Although they contain saturated fats, the latest evidence suggests that they can still support good health as part of a well-rounded, diverse diet. 

Natural yogurt and some cheeses also contain live bacteria, which can support gut health. Cheeses with live probiotics include:

• Swiss

• provolone

• aged cheddar 

• Gouda

• Edam

• Gruyère

• Parmesan

5. Add extra calories to your regular meals

Consider adding energy-dense foods to recipes you already enjoy. For instance:

• Sprinkle cheese on meals.

• Add peanut butter to sandwiches and smoothies.

• Sprinkle seeds and nuts on salads and other dishes.

• Pour olive or seed oils on salads.

• Mix full-fat yogurt with dips and sauces.

6. Start eating dessert

If you don’t already, start adding a healthy dessert to the end of every meal. Here are a few calorie-dense but still healthy options:

• Yogurt with nuts, seeds, and berries.

• A few squares of dark chocolate with a handful of nuts.

• Fruit salad with full-fat yogurt, honey, and nuts.

• Dates stuffed with peanut butter — you can dip these in chocolate or roll in coconut. 

• Homemade trail mix with popcorn, chocolate chips, nuts, and dried fruit.

• A mini cheeseboard: Cheese, crackers, chutney, and fruit.

• Toast or crackers with cottage cheese, peaches (or any stone fruit), and a drizzle of honey.

Summary

So, if you are attempting to gain weight, try to:

• Eat more healthy fats and protein.

• Listen to your hunger cues.

• Eat regular snacks and meals each day.

• Keep physically active, especially resistance and weight training.

• Add extra healthy calories to meals you already enjoy.

• Start eating dessert.

Making some of the small changes we’ve outlined above and applying them consistently will allow you to slowly increase your weight in a healthy, sustainable way.

However, if you still struggle to put on weight, or you have lost a significant amount of weight without changing your diet or lifestyle, make sure you speak with your doctor.