Gaining weight in a healthy manner without relying on tablets or supplements is possible by following these general guidelines:

1. Calorie surplus: To gain weight, you need to consume more calories than your body burns. Calculate your Total Daily Energy Expenditure (TDEE) to estimate the number of calories your body needs to maintain its current weight, and then add around 250-500 calories to create a modest calorie surplus.

1. Nutrient-dense foods: Focus on consuming nutrient-dense foods that provide a good balance of macronutrients (carbohydrates, proteins, and fats) as well as essential vitamins and minerals. Include whole grains, lean proteins, healthy fats, fruits, vegetables, and legumes in your meals.

1. Frequent meals and snacks: Increase your meal frequency and add nutritious snacks between meals to increase your calorie intake. Aim for three main meals and 2-3 snacks throughout the day.

1. Protein-rich foods: Incorporate adequate protein into your diet to support muscle growth and repair. Include sources such as lean meats, poultry, fish, eggs, dairy products, legumes, and plant-based protein sources like tofu and tempeh.

1. Healthy fats: Include healthy fats in your diet to boost calorie intake. Opt for sources like avocados, nuts, seeds, olive oil, and fatty fish.

1. Resistance training: Engage in regular resistance training exercises to stimulate muscle growth. This can involve bodyweight exercises, lifting weights, or using resistance bands. Focus on compound exercises that target multiple muscle groups, such as squats, deadlifts, bench presses, and rows.

1. Adequate rest and recovery: Ensure you’re getting enough rest and sleep to support muscle growth and recovery. Aim for 7-9 hours of quality sleep each night.

1. Stay hydrated: Drink plenty of water throughout the day to support overall health and ensure optimal bodily functions.

1. Consult a professional: If you are struggling to gain weight or have specific dietary requirements or concerns, it’s advisable to consult with a registered dietitian or a healthcare professional who can provide personalized guidance and support.

Remember that weight gain should be approached in a healthy and gradual manner. It’s important to focus on gaining lean muscle mass rather than just adding body fat. Patience, consistency, and a balanced approach are key factors in achieving sustainable weight gain.