Gaining weight is the desire of every underweight. Underweight is a term describing a person whose body weight is considered too low to be healthy. The definition usually refers to people with a body mass index (BMI) of under 18.5 or a weight 15% to 20% below that normal for their age and height group.
Body weight involves adipose tissue, fat deposits, fluids such as water and many other factors. But in low body weight there is very less adipose tissue and low fat deposits. Underweight causes skiny body and thin hair which results in hairfall.
Fat has a bad reputation for causing people to be overweight and obese. However, not all fat is bad. In fact, breaking down and storing energy (calories) as fat is good. It’s just one of the many ways the body uses food to function, heal, and grow.
Stored energy from fat helps you get through a strenuous job or workout. It plays a key role in brain development, and in preventing inflammation. Fat contributes to healthy hair and skin, as well.
Causes of underweight:-
- A person may be underweight due to genetics, metabolism, drug use, lack of food (frequently due to poverty), or illness.
- Being underweight is associated with certain medical conditions, including hyperthyroidism, cancer, or tuberculosis.
- People with gastrointestinal or liver problems may be unable to absorb nutrients adequately. People with certain eating disorders can also be underweight due to lack of nutrients/over exercise.
Weight loss is a serious issue in the India. Consumers constantly see advertisements and news reports on trendy diets, flashy products, and magic pills promising to help them lose weight.
Given that the ongoing “battle of the bulge” is front and center for so many people, being too thin may seem like a good problem to have. But the reality is that being underweight can cause health problems.
Symptoms :-
Genetics – If you’ve been thin since high school and it runs in your family, it’s likely that you were born with a higher-than-usual metabolism. You also may have a naturally small appetite.
High physical activity – If you’re an athlete, you probably know that frequent workouts can affect your body weight. However, high physical activity also can be a part of an active job or an energetic personality. If you’re on your feet a lot, you may burn more calories than people who are more sedentary (inactive).
Illness – Being sick can affect your appetite and your body’s ability to use and store food. If you’ve recently lost a lot of weight without trying, it may be a sign of disease, such as thyroid problems, diabetes, digestive diseases, or even cancer. Talk to your doctor about sudden weight loss.
Medicines – Certain prescription medicines can cause nausea and weight loss. Some treatments, such as chemotherapy, can reduce appetite and worsen weight loss from illness.
Psychological issues – Our mental well being affects every part of our lives. Things like stress and depression can disrupt healthy eating habits. Severe body image fears and distortions can lead to eating disorders. If you’re suffering from damaging emotional issues, talk to your doctor. He or she can help you get the care, assistance, or counseling you may need.
BMI chart:
You must be thinking what my weight should be. This you can see in the BMI chart that you are underweight or your weight is normal

Ayurveda View :-
In Ayurveda, your optimal weight is determined less by a number on a scale, and more by your constitution. A lighter constitution will naturally have a lower ideal body weight than someone of a similar height with a denser constitution.
Ayurveda is based on the principal of Tridoshas. Body constitution also depends upon that.
The qualities of tridosha access the constitution of body. The person is underweight or overweight depends upon the dosh which is shown and treatment is done accordingly
That being said, when it is appropriate, Ayurveda offers a number of effective strategies for building and nourishing the body that encourage a balanced approach to gaining weight. It doesn’t matter how long you’ve struggled with being underweight or if you are just looking to reset after an unusual period of stress or depletion. The Ayurvedic approach is simple, holistic, healthy, and effective.