📋 Health Information · Editorial Team
How to Gain a Stone Safely
Gaining 14 lb (6.35 kg) the healthy way: a modest calorie surplus, strength training, and nutrient-dense food, guided by NHS advice for underweight adults.
Medical disclaimer: This article is general information, not medical advice. If you have lost weight without trying, have a BMI below 18.5, or have an eating disorder, speak to your GP before attempting to gain weight. The NHS advises getting checked for underlying causes of unexplained weight loss.
Why Gaining Weight Needs a Plan Too
Being underweight carries real health risks: weakened immunity, fertility problems, fragile bones, and constant tiredness. Mumsnet threads on gaining weight describe the same frustrations as weight-loss threads in reverse: "eat more" is not helpful advice when your appetite is small or your metabolism runs fast.
The goal is not just a bigger number on the scale. The NHS advises gaining weight gradually with nutritious food and strength training, so the stone you gain is a healthy mix of muscle and energy reserves, not just body fat from junk food.
The Maths of Gaining a Stone
A stone is 14 lb, roughly 49,000 calories of stored energy. Gaining it healthily means a modest surplus:
| Daily surplus | Weekly gain | Time to gain a stone |
|---|---|---|
| +300 kcal | ~0.5 lb | ~28 weeks |
| +500 kcal | ~1 lb | ~14 weeks |
A surplus of 300 to 500 kcal per day is the NHS-aligned sweet spot: enough to gain steadily, small enough that most of the gain is lean tissue when combined with strength training. Use our BMI calculator to check whether you are underweight and how far you are from a healthy range.
NHS-Aligned Strategies for Healthy Weight Gain
1. Eat little and often
Three smaller meals plus 2 to 3 nourishing snacks beats three huge meals you cannot finish. The NHS specifically recommends eating smaller meals more frequently, with healthy snacks between meals. Keep easy options at hand: bananas, yoghurt, nuts, cereal bars.
2. Make every bite count
Add calories without adding bulk: stir peanut butter into porridge, grate cheese onto pasta, cook with olive oil, choose whole milk over skimmed, and add dried milk powder to milky drinks. NHS dietitians call this food fortification, and it is the standard clinical approach to healthy weight gain.
3. Drink your calories between meals
Smoothies and milkshakes are ideal: milk, banana, oats, peanut butter, and honey blend into 500 to 700 kcal that do not blunt your appetite for the next meal. Avoid filling up on water or fizzy drinks just before eating.
4. Strength train 2 to 3 times per week
Without resistance training, a calorie surplus mostly becomes fat. Squats, push-ups, lunges, and rows, with progressive overload, direct the extra calories toward muscle. This is also the single best way to stimulate appetite naturally.
5. Do not rely on junk food
The NHS explicitly advises against gaining weight on chocolate, cakes, and sugary drinks. They add body fat rather than lean mass and can raise blood cholesterol. Calorie-dense does not have to mean nutrient-poor: nuts, avocados, oily fish, and full-fat dairy do the job better.
A Sample High-Calorie Day
An illustrative example of how 2,800 to 3,000 kcal can look across a day of eating little and often:
- Breakfast: porridge made with whole milk, sliced banana, a tablespoon of peanut butter, and honey.
- Mid-morning: full-fat Greek yoghurt with granola and dried fruit.
- Lunch: chicken and avocado sandwich on thick wholemeal bread with a handful of nuts.
- Afternoon: banana smoothie with whole milk, oats, and peanut butter.
- Dinner: salmon with rice and vegetables cooked in olive oil, plus cheese on the side.
- Evening: toast with peanut butter and a glass of whole milk.
When to get help: if weight loss was unintentional, if you cannot gain despite eating more, or if you have symptoms like exhaustion, missed periods, or frequent infections, see your GP. They can check for thyroid problems, gut conditions, or other causes, and refer you to a dietitian.
Frequently Asked Questions
How can I gain a stone healthily?
Eat a little more than you burn: about 300 to 500 extra kcal per day, eat little and often with 2 to 3 nourishing snacks, choose full-fat dairy and calorie-dense foods like nuts and peanut butter, and do strength training so the gain is muscle, not just fat.
How long does it take to gain a stone?
A stone is 14 lb, about 49,000 calories. At a surplus of 300 to 500 kcal per day, healthy weight gain of 0.5 to 1 lb per week means 14 to 28 weeks. Gaining faster than that usually adds mostly fat.
Should I just eat junk food to gain weight?
No. The NHS advises against relying on high-calorie foods full of saturated fat and sugar to gain weight, because they increase body fat rather than lean mass and raise cholesterol. Build weight with nutritious, calorie-dense foods instead.
What are the best foods for healthy weight gain?
Porridge with whole milk and peanut butter, nuts and trail mix, full-fat yoghurt, cheese, eggs, oily fish, avocados, dried fruit, and smoothies made with milk, banana, and oats. Add milky drinks and snacks between meals.
When should I see a GP about being underweight?
See your GP if you have lost weight without trying, if your BMI is below 18.5 and you cannot gain weight, or if you have symptoms like constant tiredness, missed periods, frequent illness, or hair loss. Unexplained weight loss always deserves a check-up.