Updated March 4, 2023The majority of Americans are overweight, but some people have the opposite issue. They weigh too little instead of too much. Being underweight carries similar risks to being overweight, so it’s essential to take steps to reach and maintain a healthy weight.We created this guide for informational purposes only. You should always contact your doctor or a dietician before you make any changes to your normal diet.How Do You Define “Underweight?”Your Body Mass Index (BMI) indicates your weight, depending on your height and other factors. You’re considered underweight if your BMI is less than 18.5. The National Institute of Health has a healthy weight calculator to make it easier to determine if you’re at an appropriate weight.If you’re underweight, it might be from limited nutrition or an underlying condition. Underweight people can face a few health problems if they don’t take steps to correct any underlying issues. These health issues include:A weaker immune system. You’re more likely to fall ill if you’re underweight.Nutrient deficiencies that may evolve into more severe conditions, such as osteoporosis or anemia.Women may experience fertility issues if they’re underweight.“Weight loss and weight gain are sensitive subjects to everyone. Just because a person weighs a specific amount, or looks like they weigh a specific amount, doesn’t mean they are healthy or unhealthy,” says Brittany Ford, RHN. “It is easy to misconstrue a person’s health status by their appearance. This is especially evident for those who are underweight. While society tends to praise thinner people, a lot of underweight people are dealing with serious health conditions. These can range from eating disorders to hormonal imbalances to mental health issues,” she adds. Common Reasons for Low Body WeightBodyweight fluctuations are normal. However, if you lose more than 5 percent of your weight over 6 to 12 months with no clear explanation, it’s best to speak with your doctor about possible causes and what you might need to do to regain the weight.Weight loss is normal after a recent stressful event, such as the loss of a loved one or a significant lifestyle change. Once you’ve had time to adjust to the change and are feeling happier, your weight should return to normal. You may want to consider psychotherapy to make the transition smoother.Eating disorders are another common reason that people lose too much weight. People of all backgrounds can develop an eating disorder such as anorexia or bulimia.Other causes of unintentional weight loss include:Depression An overactive thyroid or mishandled treatment of an underactive thyroidCancerDental issues, such as chipped or cracked teeth, new orthodontics, or mouth ulcersDysphagia, or swallowing difficultiesGut problems such as stomach ulcers, Celiac’s disease, Crohn’s disease, or ulcerative colitisDementia patients who can’t communicate their hunger needsInflammatory conditions such as arthritisHeart diseaseUndiagnosed diabetesNot All Fats Are EqualMany people see all dietary fats as bad, but it’s not quite that simple. Healthy fats are a source of energy. Your body uses fats to absorb needed vitamins and minerals and build cells. Adding extra healthy fats to your diet can help with weight gain, as fat is calorically dense at about 9 calories per gram, compared to protein and carbohydrates that have about 4 calories.There’s monounsaturated and polyunsaturated fats, saturated fats, and trans fats. You’ll find healthy monounsaturated and polyunsaturated fats in fish, vegetables, nuts, and seeds, not junk food.Monounsaturated and Polyunsaturated FatsThese are the beneficial fats everyone needs to consume. Monounsaturated and polyunsaturated fats differ from each other in their carbon chain structures.Monounsaturated fats are in various oils (olive oil, peanut oil, canola oil, and certain safflower and sunflower oils), avocados, and nuts. A 1960s study conducted in the Mediterranean region was the first to link olive oil and its monounsaturated fats with reduced heart disease risk.Polyunsaturated fats are in other oils (corn oil, safflower oil, sunflower oil, walnut oil, soybean oil, canola oil), various fish (salmon, mackerel, sardines), walnuts, and flaxseeds. Eating polyunsaturated fats instead of saturated fats can lower harmful cholesterol and triglycerides.Saturated FatsSaturated fats are a common diet staple. You’ll find them in red meat, whole milk products, cheese, coconut oil, and more. They’re not quite a “good” fat, but you don’t have to entirely cut them out of your diet.Eating a lot of saturated fats can increase your total cholesterol and block your arteries. Many experts recommend limiting saturated fats to under 10 percent of your daily calorie intake.Trans FatsIf there are any fats you should avoid completely, the answer is trans fats. They have no safe levels of consumption and offer no health benefits. Ingesting trans fats can increase your risk of heart disease, stroke, diabetes, and other chronic medical conditions.Artificial trans fats are banned in the United States and other countries.Healthy Ways to Gain WeightWhen aiming to gain weight, it is very important to do so under the supervision of a professional and to address the person as a whole. Ideally, we want to look at their mental, physical and spiritual health, as well as the necessary tests that accompany these areas. “Weight gain can be done properly when the person is supported well and any underlying issues are first and foremost addressed,” says Brittany Ford. Safe weight gain isn’t just about adding in high-fat foods. That kind of diet can increase belly fat, rather than create a mix of muscle and subcutaneous fat As we mentioned earlier, some fats are healthier than others. It’s better if your food intake incorporates “good” fatty foods instead of junk food.Foods you should focus on include whole-grain products, lean proteins, nuts and seeds, fruits and vegetables, and dairy. An occasional treat is okay, but you want to be careful not to overeat sugar and saturated fat.The secret to gaining weight is to eat more calories than your body can burn. A calorie calculator can help you determine how much you need to eat to maintain your weight. Add a few hundred more calories, about 300 to 500, to safely gain weight.You should discuss with your doctor safe ways to gain weight before you make any major lifestyle changes. We’ll discuss some of the more common methods.MealsEating more meals can be a simple path toward weight gain. Instead of three regular meals, eat five to six smaller meals. You can also “fill out” a meal with some extras. Sprinkle some cheese on eggs or vegetables, or bulk up a stew with some meat or dried milk.In between meals, you can snack on nuts, fruits, avocados, and simple sandwiches.BeveragesYou may want to watch what and when you drink. Occasionally, people find their appetites are suppressed if they drink before a meal. It might be better to drink during or after a meal instead.On a related note, you shouldn’t drink too much soda, coffee, and other beverages with few nutrients and calories. Try a smoothie or even a liquid meal replacement instead.It’s also a good idea to avoid water close to bedtime. Otherwise, you might experience sleep interruptions.ExercisesEating and drinking isn’t the only way to gain weight. You can also try exercising to bulk up your muscle mass. Focusing on strength and resistance training, as well as typical aerobic activities, can further help you build up your muscles. Exercising can also increase your appetite.Did We Help?It’s important to understand that healthy weight gains may not be immediate. You may require a few days or even weeks to bulk up and reach a healthy weight. Remember that your weight shouldn’t just come from junk food but wholesome meals that build up your muscle mass and subcutaneous fat.This article is for informational purposes and should not replace advice from your doctor or other medical professional. Comments Cancel replyLeave a CommentYour email address will not be published. Required fields are marked * Comment Name Email I agree to the Terms and Conditions of this website. Δ