Diet Plan for Underweight Female: How to Gain Weight Healthily

A diet plan for underweight female readers: calorie and protein targets, best Indian foods and a 7-day chart to help you gain weight healthily.

Diet Plans9 min read By PayToHealth Editorial · October 2, 2026

Diet Plan for Underweight Female: How to Gain Weight Healthily

A good diet plan for underweight female readers adds about 300–500 extra calories a day from real, nourishing food, spreads them over 5–6 meals and snacks, and includes enough protein to build muscle rather than just fat. Paired with light strength training, this approach usually leads to a slow, steady gain of about 0.25–0.5 kg (roughly ½–1 lb) a week.

This guide explains how to check whether you really are underweight, how to work out your own calorie target, which Indian and global foods help most, and gives you a 7-day weight gain diet chart for women that you can start this week.

First, check if you are really underweight

Before following any diet plan for underweight female readers, start with numbers, not the mirror.

The most common screening tool is Body Mass Index (BMI). For adults, the CDC classes a BMI below 18.5 as underweight and 18.5 to under 25 as a healthy weight. BMI is only a screening measure, though. It does not tell you how much of your weight is muscle, fat or bone, so use it as a starting point, not a final verdict. People of South Asian background tend to carry more body fat at the same BMI, so if you are Indian you can also check our Asian BMI calculator.

When to see a doctor before you start

Being underweight is sometimes simply your natural build. But the NHS advises seeing a doctor if you have lost weight suddenly, lost weight without changing your diet or exercise, or if you are using food control to cope with your emotions. Other reasons to get checked include:

Very low appetite, constant tiredness or frequent illness
Missed or very irregular periods
Stomach problems such as ongoing diarrhoea, bloating or pain after meals

Conditions such as an overactive thyroid, digestive problems, infections or an eating disorder need proper diagnosis and treatment. A diet plan helps, but it cannot replace that care.

How many calories do you need to gain weight?

Weight gain happens when you regularly eat a little more energy than your body uses. The NHS suggests that adults who want to gain weight gradually could add around 300 to 500 extra calories a day. That is roughly one extra small meal, not a feast.

Step 1: estimate your daily needs

Your body burns energy just to keep you alive. This is called your Basal Metabolic Rate (BMR). A widely used formula for it is the Mifflin–St Jeor equation. For women:

BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) − 161

Example: Priya is 25 years old, 160 cm (5 ft 3 in) tall and weighs 45 kg (99 lb). Her BMR is 450 + 1,000 − 125 − 161 = about 1,164 kcal. Her real daily needs are higher than this because she also walks, works and moves around. The easiest way to get that full number is to use our free calorie calculator, which adds your activity level for you.

Step 2: add a small surplus

Once you know your daily maintenance calories, add 300–500 kcal. Start at the lower end if you have a small appetite. Weigh yourself once a week, at the same time of day. If your weight has not moved after two to three weeks, add a little more food. If you are gaining faster than about 0.5 kg a week, cut back slightly, because very fast gain is mostly fat.

If you would rather skip the maths, our weight gain diet plan generator builds a 7-day menu from your height, weight, age and food preferences.

Protein and strength training: gain muscle, not just fat

The aim of a healthy weight gain diet plan for women is to add strength, energy and healthy curves, not a soft belly. That needs two things working together: enough protein and some resistance exercise.

How much protein?

The International Society of Sports Nutrition suggests about 1.2–1.6 g of protein per kg of body weight a day for people doing regular strength training. For a 45 kg woman, that works out to roughly 54–72 g of protein a day. You can check your own number with our protein calculator.

Spread protein across the day instead of eating it all at dinner. Aim to include a protein food at every main meal and at least one snack.

Easy strength training for beginners

You do not need a gym. Two to three short sessions a week at home can make a real difference:

Squats or sit-to-stand from a chair
Wall or knee push-ups
Glute bridges
Rows using a backpack filled with books
Lunges while holding water bottles

Start with 1–2 sets of 8–12 slow repetitions. Avoid hours of cardio, which burns the extra calories you are adding.

Best foods for a diet plan for underweight female readers

The best weight gain foods are “energy dense”, meaning they pack a lot of nutrition and calories into a small portion. That matters when your appetite is small. The NHS suggests foods such as cheese, nuts and seeds, milky drinks between meals, and protein foods like beans, pulses, fish, eggs and lean meat.

Indian foods to lean on

Milk and curd: full-fat milk, dahi, lassi, and milk-based dishes like kheer, sheera or daliya cooked in milk.
Paneer and cheese: paneer bhurji, paneer paratha, paneer tikka, cheese on toast.
Dals and legumes: rajma, chole, moong, masoor, sprouts chaat, besan chilla.
Whole grains: roti with a little ghee, poha, upma, rice, millets like ragi and bajra, oats.
Nuts and seeds: almonds, walnuts, cashews, peanuts, til, flaxseeds, peanut chikki, dry fruit laddoo.
Healthy fats: a teaspoon of ghee on roti or dal, groundnut or mustard oil for cooking, coconut in chutney.
Starchy vegetables: potato, sweet potato, arbi, green peas, corn.
Fruits: banana, chikoo, mango, dates, figs and raisins.
Non-veg options: eggs, chicken curry, fish curry, egg bhurji.

Global options

Peanut butter on whole-grain toast, overnight oats with milk and nuts, hummus with pita, Greek yogurt with granola, avocado, trail mix and homemade fruit smoothies all work well too. For a longer list, see our guide to healthy weight gain foods.

Simple calorie boosters

Add a spoon of ghee or butter to hot dal, khichdi or roti.
Stir nut powder or peanut butter into porridge, smoothies or milk.
Top poha, upma and salads with roasted peanuts or seeds.
Choose paneer or egg stuffing in parathas.
Drink milk or lassi instead of tea with a biscuit.

7-day weight gain diet chart for women (Indian)

Here is a sample weight gain diet chart for women that works as a simple diet plan for underweight female readers. It is built on normal Indian home food with extra protein and healthy fats. Portions depend on your needs, so adjust them to your calorie target. Vegetarians can swap any egg or non-veg item for paneer, tofu or dal.

Day	Breakfast	Mid-morning	Lunch	Evening snack	Dinner	Bedtime
Mon	2 paneer parathas with curd	Banana + handful of almonds	Rice, rajma, cucumber raita, salad	Peanut chikki + masala milk	2 rotis with ghee, palak paneer, dal	Warm milk with dates
Tue	Vegetable poha with peanuts + glass of milk	Mango or chikoo lassi	2 rotis, chole, jeera aloo, salad	Sprouts chaat with paneer cubes	Vegetable khichdi with ghee + kadhi	Dry fruit laddoo + milk
Wed	2 besan chillas with mint chutney + curd	Banana smoothie with oats and peanut butter	Rice, sambar, beans poriyal, curd	Roasted chana + a handful of cashews	2 rotis, egg curry or paneer bhurji, dal	Turmeric milk
Thu	Oats porridge in milk with nuts and banana	2 boiled eggs or a paneer sandwich	Jowar or bajra roti, dal, lauki sabzi, curd	Sweet potato chaat	Vegetable pulao, raita, dal	Warm milk + 2 figs
Fri	Upma with vegetables and peanuts + milk	Fruit bowl with curd and seeds	2 rotis, fish or soya curry, rice, salad	Ragi laddoo + buttermilk	Paneer paratha, dal, curd	Almond milk (homemade)
Sat	2 idlis + sambar + coconut chutney + milk	Handful of trail mix	Rice, moong dal, bhindi sabzi, curd	Peanut butter toast + banana	2 rotis, chicken curry or rajma, salad	Kheer (small bowl)
Sun	Moong dal chilla with paneer stuffing + lassi	Dates and walnuts	Chole with rice, raita, salad	Corn and paneer sandwich	Vegetable daliya khichdi with ghee + curd	Warm milk with nut powder

Everyday habits that make weight gain easier

Knowing how to gain weight for women is often less about special foods and more about daily routine. These small habits help:

Eat every 3–4 hours. The NHS suggests smaller meals more often, with healthy snacks in between. Set phone reminders if you forget to eat.
Drink some of your calories. Milk, lassi, smoothies and milkshakes are easier to take in than a large plate when your appetite is low.
Keep ready snacks nearby. Nuts, chikki, roasted chana, fruit and laddoos in your bag or desk make it easy to add calories.
Rest and relax. Good sleep and lower stress help keep your appetite steady.

Mistakes to avoid when gaining weight

It is tempting to reach for chips, cold drinks, sweets and fried snacks because they are high in calories. They can add weight, but mostly as fat, and they offer little of the iron, calcium, protein and fibre an underweight body often lacks. The NHS notes that being underweight can mean you miss out on vitamins and minerals, which may affect your immunity and bone health. So the goal is extra nourishment, not just extra calories.

Other common mistakes:

Skipping breakfast. It is one of the easiest meals to add calories and protein.
Relying on “weight gainer” powders without advice. Food can usually do the job. Speak to a doctor or dietitian before using supplements.
Expecting fast results. A healthy pace is slow. Gaining 2–4 kg (4–9 lb) over a few months is real progress.
Giving up after one bad week. Appetite goes up and down. Look at your trend over a month, not a single day.
Ignoring iron. Many Indian women are anaemic, which can cause tiredness and low appetite. Include green leafy vegetables, dals, jaggery-based snacks and vitamin C foods, and ask your doctor about a blood test if you feel exhausted.

If you recently had a baby and want to regain strength, read our guide on healthy weight gain after pregnancy, because needs are different while breastfeeding.

Make it personal: get a free 7-day weight gain diet plan for women based on your height, weight and food preferences with our weight gain diet plan generator, and find your daily target with the calorie calculator.

Frequently asked questions

How fast can an underweight woman safely gain weight?

A steady pace of about 0.25–0.5 kg (½–1 lb) a week is a sensible target. That usually comes from eating 300–500 extra calories a day. Faster gain is possible but tends to be mostly fat. Check your weight once a week and adjust your food slowly instead of making big jumps.

What should I eat at night to gain weight?

A small, nourishing bedtime snack helps add calories without upsetting sleep. Good options are warm milk with dates or nut powder, a small bowl of kheer or daliya, a banana with peanut butter, or curd with a few nuts. Keep it light if you have acidity, and eat at least an hour before lying down.

Can I gain weight on a vegetarian diet?

Yes. Paneer, milk, curd, dals, rajma, chole, soya, tofu, nuts, seeds and whole grains give plenty of protein and energy. Combine a grain with a pulse, such as dal-rice or roti-rajma, at main meals, and include a milk or paneer item most days to reach your protein target.

Is it normal to feel full quickly when trying to gain weight?

Yes, many naturally thin women feel full fast. Eat smaller amounts more often, choose energy-dense foods like nuts, ghee, paneer and milk drinks, and avoid drinking a lot of water just before meals. Appetite usually improves over a few weeks. If it stays very low, see a doctor.

Do I need a weight gainer supplement?

Most women can gain weight with normal food alone. Supplements are not needed for everyone and some contain a lot of sugar. If you have a medical condition, very poor appetite or trouble eating enough, talk to your doctor or a registered dietitian before trying any powder or pill.

Sources

This article is for general information and is not a substitute for medical advice. Please talk to your doctor or a registered dietitian about your own health, especially if you are pregnant, breastfeeding or have a medical condition.

PayToHealth Editorial

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Medical disclaimer. This article is for general information and is not a substitute for professional medical advice, diagnosis or treatment. If you have symptoms or concerns, please see a qualified doctor.