While two out of three people in America are overweight or obese, there is another group of people who are too thin. (1)
Girls and women are 2 to 3 times as likely to have problems with being underweight than men and boys. (2)
Low body weight can be just as much of a health liability as being overweight. And some people who don’t classify as clinically underweight have a difficult time putting on muscle.
Safe and proven strategies for gaining weight depend on the same basics, regardless of which group you fall into.
How Being Underweight Affects Health
Body size is gauged by measuring body mass index (BMI); you can calculate your BMI by plugging in vital statistics at this site.
Here’s the breakdown:
- 5 BMI or less is considered underweight; experts believe this size can’t support optimal physical function.
- BMI of more than 25 is classified as overweight
- Those with a BMI higher than 30 are obese
Using the body mass index calculator isn’t always accurate, because it’s based on height and weight; muscle mass is not taken into consideration.
It’s not always an indication of poor health to be underweight, but it can cause problems for certain individuals.
One study indicated that a low BMI increases the risk of premature death by 100% in women and 140% in men. (3)
In the same study, being obese raised the risk of premature death by 50%, so it’s possible being underweight could have more adverse health effects than carrying large amounts of extra weight. (4)
However, results from a different study suggested that being underweight could be more risky for men than for women; this one showed underweight men were more likely to die at a younger age, but women were not. (5)
Common Reasons for Being Underweight
A range of medical conditions can lead to weight loss. For anyone who has lost a significant amount of weight without making an effort, it’s important to see your doctor and determine whether you have a serious condition.
These are some of the reasons people become underweight:
- Cancerous tumors require massive quantities of calories and sometimes lead to excessive weight loss.
- Celiac disease results from a severe intolerance to gluten, and a majority of the people suffering from this problem don’t realize it. (11)
- Eating disorders like anorexia nervosa, which is a mental illness, can cause extreme reductions in body weight.
- Suffering from uncontrolled diabetes, most often type 1, sometimes leads to weight loss.
- Hyperthyroidism, which results from an overactive thyroid gland, boosts metabolism to the point where unhealthy weight loss occurs.
- Infections can also cause significant weight loss, including tuberculosis, HIV/AIDS and parasitic infections.
Gaining Weight the Right Way
Adopting a healthy lifestyle, including eating the right foods, is just as important for gaining weight as it is for losing weight.
It’s possible to be of normal weight and still have serious health issues, including heart disease and type 2 diabetes, which is one of the reasons it pays to strategic when you set out to gain weight. (12)
Eating the type of foods normally associated with weight gain, like sugary drinks or pastries, is likely to result in packing a lot of fat around your organs; this belly fat puts you at a higher risk for developing chronic diseases. (13)
Consuming more calories than your body needs for maintenance and energetic requirements related to activity levels is essential. If you don’t overfeed yourself, you won’t gain weight.
You can get a clear idea of how many calories your body requires by using this calculator.
This will give you a range of caloric requirements to work with, although needs can vary by several hundred calories daily, so adjustments along the way may be necessary.
Some people only need to track calories for a few days to find the range of intake they need, while others might have to do it for a few weeks.
For slow and steady weight gain, add 300 to 500 calories daily; for fast weight gain, shoot for 700 to 1000 calories above your requirements.
Making sure your diet is high in protein is the best way to put on healthy weight, because muscle mass is built with protein. (14)
Eating between 0.7 and 1 gram of protein for each pound of body weight is a good guideline for gaining.
Include plenty of high protein foods like eggs, fish, meats, nuts, legumes and dairy products. Add a whey protein supplement for extra protein.
It’s also important to eat plenty of carbohydrates and healthy fats, and you’ll do best with weight gain if you eat three full meals daily, as well as a couple of energy-dense snacks.
Whole, natural foods are the best choice, but many people run into the same problem with these foods as with protein: they’re extremely filling and can make it hard to eat enough calories.
Look over this list of foods that pack a punch when it comes to energy:
- Grains: stick with whole grains like brown rice and oats
- High-fat dairy products: cream, cheese, whole milk, and full-fat yogurt
- Oils and fats: the best choices are avocado oil and extra virgin olive oil
- Meat: fattier cuts of beef, pork and lamb; chicken with skin left on
- Tubers: yams, sweet potatoes and potatoes
- Dried fruit: prunes, dates and raisins, etc.
- Nuts: macadamia, almonds, peanuts and walnuts
Other good foods to include are avocados, dark chocolate, granola and trail mix, peanut butter and coconut milk.
Because these foods are filling, many people find it easier to hit caloric goals if they don’t eat a large amount of fruits and vegetables while working on weight gain.
As long as you don’t have any health conditions that prevent it, lift weights 2 – 4 times weekly; this will help insure the extra calories go to muscle building. A limited amount of cardio work for health is fine, but don’t overdo it.
Gaining weight can be challenging and making significant changes will take time. New eating patterns alter hormonal activity, and the brain can be very resistant to weight changes, whether you’re going up or down.
Summary: For those who are underweight, significant health benefits can be realized by adding extra pounds when it’s done properly; choose natural, whole foods that are energy-dense, and remain consistent with overfeeding and weight-lifting to see those numbers on the scale climb.