Weight Loss With Intermittent Fasting: How Many Kilos Are Lost Per Month?

Although intermittent fasting can improve metabolic health, not everyone responds equally. Here are the key medical recommendations.

16-hour intermittent fasting, also known as the 16:8 method, has emerged in recent years as one of the most popular strategies for losing weight and improving metabolic health.

However, its daily practice raises questions: Is it safe to do it every day? What benefits does it offer, and what risks might it entail?

How does 16-hour intermittent fasting work? The process is simple: you establish 16 hours without eating, and concentrate all your meals during the remaining 8 hours.

A common example is stopping eating at 8:00 PM and starting again at noon the next day. During the fast, only calorie-free liquids, such as water, black coffee, tea, or unsweetened herbal teas, are allowed.

According to personal trainer Natalia López, it’s recommended to start gradually. “If you’ve never tried it, start with 12 hours and gradually increase. Listen to your body and stop if you feel dizzy or weak,” she advises.

Medical recommendations before starting

Dr. José Manuel García Almeida, an endocrinologist at Quirónsalud Málaga Hospital, emphasizes the importance of a prior medical checkup. “Intermittent fasting is not suitable for everyone. Patients with diabetes, pregnant women, or people with a history of eating disorders should exercise special caution,” he points out.

She also emphasizes that the benefits of 16-hour intermittent fasting depend on maintaining a balanced diet during the eating window. Otherwise, there is a risk of developing nutritional deficiencies.

What if it is done every day?

Performing intermittent fasting daily can improve insulin sensitivity, improve glucose control, and stimulate fat burning. However, if not planned properly, it can also increase food cravings and lead to binge eating.

On a metabolic level, prolonged fasting activates ketosis, a mechanism by which the body uses fat reserves as an energy source. Although this can be positive, not everyone responds equally, which is why some specialists recommend alternating fasting days with normal eating.

Weight loss with the 16:8 method

One of the most common motivations for adopting this practice is weight loss. According to experts, weight loss depends on a calorie deficit, diet quality, and physical activity. On average, those who follow 16-hour intermittent fasting can lose between 1 and 4 kilos per month, provided they accompany it with exercise and a healthy diet.

What should you eat and what should you avoid?

In the feeding window, the key is to choose nutritious foods: high biological value proteins (chicken, fish, eggs), complex carbohydrates (oats, quinoa, whole-grain bread), and healthy fats (avocado, nuts).

Nutritionist Lara Dalla Rovere recommends avoiding ultra-processed foods and refined sugars. “Breaking the fast with a nutritious meal helps maintain stable energy and control appetite,” she explains.

Examples of suitable foods are:

Lunch: Spinach salad with grilled salmon and quinoa.
Snack: natural yogurt with nuts.
Dinner: Light vegetable cream soup with shredded chicken.

As for beverages, only calorie-free liquids, such as tea, black coffee, or water, are allowed during the fast. Options like unsweetened kombucha or water kefir are also acceptable. However, milk, juice, or any solid food breaks the fast.

Is it better to skip breakfast or dinner?

There’s no single answer. The choice depends on each person’s habits. However, from a hormonal perspective, eating dinner early and avoiding heavy meals at night can promote rest and regulate circadian rhythms.

Meal ideas to break and end the fast

Post-fast breakfast: scrambled eggs with avocado and whole-wheat bread, or a green smoothie with spinach and banana.
Light dinner: salad with chicken or turkey, steamed vegetables, and a small portion of nuts.

According to nutritionist Dalla Rovere, foods rich in tryptophan, such as turkey and bananas, help improve sleep quality thanks to the production of serotonin.