Concerned About Being Extremely Underweight – Seeking Advice on Healthy Weight Gain - #12335
Hi doctor, I’m a 17-year-old male, 6 feet tall, and I weigh about 48 kg (106 lb). I’ve always been very thin, but lately I’m starting to worry that my weight is too low. I often feel tired and weak. I’d like to know what could be causing this and what steps I can take to safely gain weight and build muscle. Are there any specific dietary changes, exercises, or tests you would recommend? Thanks!
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Doctors’ responses
Hello dear Yes as per bmi guidelines you are quite young Iam suggesting some precautions Please follow them for atleast 2 months Do weight gaining exercises like vajrasana and surya namaskar Eat grams and cheese in between meals Consume staple diet Avoid synthetic supplements Take zincovit multivitamin onca a day for 2 months Take products of desi ghee for fat buid up In addition get following tests done Serum RBS Serum tsh Serum ferritin In case of no improvement in 1 month consult dietician in person for better clarity Hopefully you improve Regards Serum
Hello, Weight loss need to be evaluated properly. Get these tests done: 1. CBC 2. Thyroid profile 3. BMI with Protein and Fat index 4. VITAMIN-B12 5. VITAMIN-D3
Review with reports. Consult a dietician for a protein specific diet chart.
Take care
Hello Alejandro, I understand that this might be worrisome. Your BMI is around 14.5, which is underweight. Here is my advise -
1.Recommended Blood Tests - CBC, FT3, FT4, TSH, Fasting blood sugar, Vitamin B12, Vitamin D, Ferritin, Stool routine (for worms or malabsorption).
2. Diet Plan to Gain Weight Safely - -Aim for 5–6 small, high-protein, high-calorie meals/day. -Eat about 500–700 extra calories/day than your current need. -Morning (Breakfast): Milk + banana / mango shake with nuts. 2 boiled eggs or paneer/tofu. 2 slices peanut-butter toast -Lunch: Rice / chapati + dal / chicken / paneer. Add 1 tsp ghee or olive oil to food. Salad + curd. -Evening Snack: Smoothie (banana + oats + milk + peanut butter). Handful of almonds, walnuts, or roasted chana -Dinner: Protein-rich meal (paneer, lentils, tofu, or fish). Rice or whole-wheat chapati + veggies -Before Bed: 1 glass warm milk with Protein Powder (Muscle blaze beginner protein if not working out, if working out then Only What’s Needed whey protein) -Drink enough water, but avoid filling up on liquids before meals.
3. Exercise Plan - Do strength training / resistance exercises 4–5 times per week – push-ups, squats, light weights, resistance bands. → Builds muscle, not fat. Avoid too much cardio. Sleep 7–8 hours daily for recovery and hormone balance.
4. You can take this supplement prescription - - Tab. Multivitamin once daily × 3months -Tab. Albendazole 400mg single dose
5. When to physically See a Doctor - Sudden unexplained weight loss. Persistent fatigue, palpitations, or tremors. Chronic diarrhea or loss of appetite.
Feel free to reach out.
Regards, Dr. Nirav Jain MBBS, DNB D.Fam.Med
Investigation: 1) CBC 2) Thyroid profile 3) Vitamin B12 and D3 4) Fasting sugar 5) Stool RE and ME
Underweight likely due to calorie deficit or fast metabolism. Focus on 3000 kcal/day + strength training + sleep. Get basic blood & thyroid tests done. Weight will rise gradually and safely in 6–8 weeks.
Hi Dear Alejandro , Kindly donot worry Its not bad to be thin Kindly do certain tests before starting your diet Kindly do RBS ,FT3 FT4 TSH , USG A+P , Hb Kindly take good fats , protien rich diet kindly donot stress take care
Hi Alejandro,
You’re still growing, so with the right support, you can absolutely gain weight safely and build strength.
First we have to rule out whether this is due to any medical reason.For that you have to do some tests:
1.Thyroid profile 2.CBC 3.LFT/RFT 4.Stool routine and culture
Meanwhile: Follow calorie dense diet+ strength training exercises 1.Frequent meals 2.Take Calorie-dense foods such as peanut butter,nuts,almonds,Milk,Eggs,potatoes 3. High-calorie shakes/smoothie 4.Whey protein
Supplements: Omega 3 Zinc+multivitamin
For appetite: Syp: Megestrol 125mg 5ml once a day
I hope this helps Feel free to talk Thank you
Hello dear Practical steps to reach a healthier weight safely-
1)Get a medical checkup - Ask a clinician to check vitals, growth charts, basic labs (CBC, iron studies, TSH, metabolic panel, celiac screen, vitamin D) and activity level.
2)Track current intake briefly - Record everything you eat for 3–7 days (portion sizes). This reveals gaps in calories, protein and nutrients without relying on memory.
3)Increase daily calorie intake in a structured way - Add 300–500 kcal/day as a starting goal; aim for gradual weight gain of 0.5–1 lb/week. - Prefer nutrient-dense, calorie-dense options: nuts and nut butters, avocados, whole-fat dairy (or fortified plant alternatives), olive oil, hummus, smoothies with milk/yogurt/banana/oats/protein powder.
4)Prioritize protein and resistance exercise - Target ~1.2–1.6 g protein/kg body weight (about 55–75 g/day for your weight) to support muscle gain. - Add 2–4 sessions/week of progressive resistance training (bodyweight progressing to weights) to convert extra calories into lean mass.
5)Eat more frequently and add small boosts - 3 meals + 2–3 snacks; add a bedtime snack like yogurt with granola or peanut butter on toast. - Mix liquids and solids (smoothies, meal-replacement shakes) if large meals feel hard to eat.
6)Monitor progress and adjust - Weigh weekly at the same time; aim for steady upward trend. If no change after 4–6 weeks, increase calories further or consult a dietitian.
7)Consult professionals - Registered dietitian (preferably pediatric or adolescent experience) for meal plans and portion guidance. - If labs or symptoms suggest medical causes, follow up with appropriate specialists (endocrinology, gastroenterology).
Thank you
1. Being 6 feet tall and 48 kg means your BMI is quite low, suggesting calorie deficit or possible nutrient malabsorption.
2. First, rule out causes like thyroid imbalance, vitamin D or B12 deficiency, anemia, or intestinal issues through basic blood tests.
3. Eat every 3 hours include 5–6 high-calorie meals daily with foods like rice, potatoes, paneer, eggs, bananas, peanut butter, and milkshakes.
4. Add healthy fats such as ghee, nuts, seeds, and olive oil to every meal for steady calorie gain.
5. Include protein-rich foods like eggs, chicken, lentils, and curd to build muscle mass.
6. Start light strength training or resistance workouts they help convert calories into lean muscle instead of fat.
7. Sleep at least 8 hours and avoid skipping meals; consistency is key. With proper diet and exercise, expect visible results in 6–8 weeks.
Being underweight can be concerning, especially if you’re experiencing symptoms like tiredness and weakness. Several factors might be causing your low weight, including a high metabolism, dietary insufficiencies, or even underlying medical conditions. Conditions such as hyperthyroidism, malabsorption disorders like celiac disease, or even diabetes can sometimes manifest with weight loss or difficulty gaining weight, so it would be wise to consider seeing a healthcare provider to rule these out with appropriate tests — they might suggest a thyroid function test, complete blood count, or even investigative imaging if needed to get to the bottom of it. On the dietary front, increasing your caloric intake is key. Focus on nutrient-dense foods that are rich in healthy fats, like nuts, seeds, avocados, and olive oil. Incorporating more complex carbohydrates, such as whole grains, and high-protein foods like lean meats, fish, eggs, and legumes could also be beneficial. Eating smaller, more frequent meals throughout the day can make it easier to increase overall intake. Strength training exercises are useful for building muscle mass. Joining a gym and working with a trainer to create a personalized routine can be effective—focusing on resistance exercises for major muscle groups a few times a week could help with muscle gain. Avoid excessive cardio, as it might counteract weight gain efforts. Consider keeping a food and activity journal to help monitor progress and make adjustments as needed. If circumstances allow, consulting a dietitian or nutritionist might provide more tailored guidance based on specific caloric needs and lifestyle. Prioritizing adequate sleep and stress management is also important, as physical and mental health are closely linked with weight. If any new concerning symptoms arise, or you do not see any progress despite these efforts, further medical intervention might become necessary.
Hello dear Kindly follow this 1. Eat More Calories Than You Burn • Use a calorie calculator to estimate your daily maintenance needs. • Add 300–500 calories/day for slow, steady gain. • Add 700–1,000 calories/day for faster gain.
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2. Prioritize Protein
Protein helps build muscle (not just fat). Aim for 1.6–2.2 g of protein per kg of body weight. Good sources: • Chicken, beef, fish, eggs • Greek yogurt, milk, cheese • Lentils, beans, tofu, tempeh
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3. Eat Calorie-Dense Foods
Instead of just eating larger volumes, choose foods rich in calories and nutrients: • Nuts & nut butters (almonds, peanut butter, cashews) • Avocados • Whole grains (oats, quinoa, brown rice) • Dried fruits (dates, raisins, figs) • Healthy oils (olive oil, coconut oil, ghee)
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4. Strength Training • Focus on compound lifts: squats, deadlifts, bench press, pull-ups. • Train 3–5 times per week. • Muscle growth ensures the weight you gain isn’t just fat.
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5. Eat Frequently • 5–6 meals/snacks per day instead of 2–3 big meals. • Add calorie boosters to meals: cheese on eggs, nut butter in smoothies, olive oil drizzled on veggies.
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6. Drink Calories • High-calorie smoothies/shakes can help when you don’t feel like eating. • Blend: milk, protein powder, peanut butter, oats, banana, and honey.
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7. Rest & Sleep
Muscles grow while you rest, not just while training. Aim for 7–9 hours of sleep each night
Being underweight at your height could be due to high metabolism, poor nutrition, or underlying medical issues. A balanced diet rich in proteins, complex carbs, and healthy fats along with strength training can help increase weight safely. Specialist consultation is advised (Physician or Dietitian).
Just follow the balanced diet food pattern which helps in gaining weight. Protein and fat rich diet is advisable but it should be the balanced with micro and macronutrients. Suggesting few: Avacados, Soaked nuts, carrot milkshake, apple milkshake Remember always follow balanced diet plan!
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