Comment éviter de prendre du poids en été : 6 conseils pour votre métabolisme

Summer does not make you gain weight, but your habits can.

We all know that person.

September arrives and they say:

“I had such a great summer, but I gained 5 kilos.”

And then they immediately begin:

• I’ll start on Monday.
• No bread.
• No beer.
• Two hours at the gym every day.

As if August had been a crime.

The funny thing is that the problem is rarely the holiday itself. The problem is thinking that anything goes for fifteen days and that we will simply fix it later.

Your metabolism does not work like that. Neither does your body.

That is why we are going to share some basic tips you can apply during the summer and, even better, turn into part of your lifestyle.

1. Do not arrive at dinner starving

You have probably done this too.

You know you have a big dinner coming up, so you barely eat all day to “make up for it”.

The problem: you end up eating far more at dinner, late at night.

Why can eating at night contribute to weight gain?

It is not because the body suddenly “stops burning calories” after a certain time. The problem appears when food intake is repeatedly shifted towards biological night, when the body is preparing to rest rather than manage a large influx of energy.

It is not only what we eat that matters. Metabolism also responds to when we eat.

There are six main reasons why regularly eating at night may disrupt the body and contribute to weight gain:

• The body works according to biological clocks.
• We generally manage glucose less efficiently at night.
• Night-time fat oxidation may decrease.
• Hunger may increase.
• Sleep may worsen.
• We tend to eat differently at night.

Our body operates through biological clocks that coordinate metabolism, digestion, appetite and rest.

During the first part of the day, we usually manage glucose more effectively and respond with greater insulin sensitivity.

At night, melatonin prepares the body for sleep and may temporarily reduce insulin secretion.

Eating late and eating a large meal sends a signal of activity at the same time as the brain is switching into rest mode.

When this happens regularly, it may disrupt internal rhythms and reduce night-time fat oxidation.

Late eating may also increase hunger, modestly reduce energy expenditure and make it more difficult to sleep.

Poor sleep can lead to greater appetite, tiredness, cravings and less physical activity the following day.

Alcohol, snacks, screens and less mindful portions are also more common at night.

Therefore, it is not “the time” alone that causes weight gain, but rather the combination of circadian disruption and excess energy intake.

So, does eating dinner late make you gain more weight?

With the same calorie intake, meal timing may affect hunger, glucose control, energy expenditure and fat use. However, total energy balance, diet quality, sleep, physical activity and chronotype remain key factors.

Eating dinner late occasionally will not disrupt your metabolism. The problem arises when regularly consuming a large proportion of your daily energy intake during biological night.

Practical recommendations

• Eat a larger proportion of your food during your active hours.
• Try to finish dinner around 2–3 hours before going to bed.
• Keep relatively regular meal times.
• Avoid making dinner your largest meal every day.
• When eating late, choose a lighter meal with protein, vegetables and a moderate amount of fat.
• Avoid restricting food too heavily during the day, as this may lead to intense hunger at night.
• If you are genuinely hungry before bed, eating something small will not “damage” your metabolism. Natural yoghurt, kefir, fruit or a small protein-based snack can be reasonable options.

2. Make sure protein is always included

You have probably experienced this too.

You arrive at the beach bar saying:

“I’m going to eat something light today.”

Twenty minutes later:

• Fried calamari.
• Potatoes.
• Beer.
• Ice cream.

And then you say:

“Well, I’m on holiday.”

That may be true, but protein should not be on holiday.

Why can protein help regulate weight?

There are five main reasons:

• It supports satiety.
• It has a higher thermic effect.
• It helps protect muscle mass.
• It supports body composition.
• It helps structure and stabilise meals.

Protein usually produces greater satiety because it supports gut signals such as GLP-1, PYY and cholecystokinin, and may reduce ghrelin, often referred to as the hunger hormone.

This may help you feel less hungry before your next meal, control portion sizes and reduce snacking.

The body also uses more energy to metabolise protein than it does to process carbohydrates or fats.

This thermic effect is real, but modest: protein does not act as a “fat burner”.

Its main advantage is that it can make your diet more filling and easier to maintain over time.

During weight loss, an adequate protein intake can help preserve muscle mass, particularly when combined with strength training.

Preserving muscle supports strength, function, insulin sensitivity and resting energy expenditure.

Adding protein to meals that contain carbohydrates may also slow gastric emptying and prolong satiety.

That is why regulating weight is not simply about weighing less. It is about losing fat while preserving muscle.

How much protein should you include?

As a practical guideline, you may aim for approximately 25–30 grams of protein at each main meal, particularly if you are physically active, going through menopause or trying to lose fat while preserving muscle.

Approximate examples include:

• 120–150 g of fish.
• 120–150 g of chicken or turkey.
• 2 eggs accompanied by yoghurt, fresh cheese or legumes.
• 200–250 g of high-protein yoghurt.
• A serving of tofu or tempeh.
• Legumes combined with tofu, eggs, fish or whole grains.
• Protein powder when it is difficult to meet your needs through food alone.

Not everyone needs exactly 30 grams at every meal. It is a useful reference, not a strict requirement.

The most common mistake: adding without replacing

Protein can help when it improves the overall structure of your diet. However, if you simply add:

• Shakes.
• Protein bars.
• Cheese.
• Nuts.
• Products labelled as “high protein”.

Without changing anything else, you may also significantly increase your total energy intake.

The aim is not to add protein indiscriminately, but to build each meal around an appropriate source of protein.

The weight-regulating plate

A simple structure could be:

• Protein: fish, eggs, poultry, legumes, tofu, tempeh or natural dairy products.
• Vegetables: approximately half the plate.
• Fibre or quality carbohydrates: legumes, potatoes, sweet potatoes, brown rice or whole grains.
• Healthy fats: extra virgin olive oil, avocado, seeds or nuts.
• Water: as your main drink.

Remember: protein works best when combined with fibre, movement and strength training.

3. Walk after eating

Ten minutes. You do not need to run a marathon every time you eat.

Your muscles can use some of the glucose from your meal, helping to reduce the post-meal glucose spike.

Why does it work?

• Muscle acts as a glucose sink.
• Duration is not the only factor: timing also matters.
• It may support digestive comfort.

Walking after a meal activates the muscles and helps them use some of the glucose circulating in the blood, which may reduce the glucose spike and insulin demand.

Glucose uptake by muscle can also increase through mechanisms linked to muscle contraction. This is why moving after meals may be particularly useful for people with diabetes, although the habit can benefit the general population as well.

Timing matters: starting immediately after eating or within the first 30 minutes may be especially helpful.

Even a gentle ten-minute walk may produce measurable improvements. It also interrupts sedentary time and increases daily movement.

Three ten-minute walks already add up to 30 minutes of daily activity and may indirectly support weight regulation by improving insulin sensitivity.

Walking may also support intestinal movement and reduce feelings of heaviness in some people.

If you experience reflux, pain or have eaten a very large meal, walk slowly and avoid intense exercise.

However, walking does not “burn off” or cancel out a meal, nor does it cause weight loss on its own.

Its real value comes from repeating the habit and combining it with strength training, adequate rest and a balanced diet.

4. Do not drink your calories without noticing

• Soft drinks.
• Cocktails.
• Slush drinks.
• Juices.
• Smoothies.

You do not need to ban them completely. You simply need to be aware that they can significantly increase daily energy intake and generally provide less fibre, less protein and less satiety than solid foods.

Why do I not feel full?

• The brain may register liquid calories less effectively.
• Sugars are absorbed quickly.
• Drinking fruit is not the same as eating whole fruit.
• Alcohol provides energy and may affect food choices.

Caloric drinks are usually less filling than solid foods because they are consumed quickly, require little chewing and stay in the stomach for less time.

They may also contain free sugars that are rapidly absorbed, particularly when consumed on their own.

Their calories tend to be added to a meal rather than replacing part of it.

In a short period of time, we can drink a large amount of energy without proportionally reducing what we eat afterwards.

A smoothie, juice or blended drink is not equivalent to whole fruit. Juice provides vitamins, minerals and polyphenols, but contains less fibre, is consumed more quickly and is less filling than the whole fruit.

Therefore, juice is not necessarily the same as a soft drink, but it is also not the same as eating the whole piece of fruit.

Alcohol provides approximately 7 kcal per gram, while cocktails may also contain sugar, syrups, juices and soft drinks.

Alcohol may temporarily reduce fat oxidation, disrupt sleep and encourage impulsive food choices.

Practical option: drinks that add enjoyment, not calories

When you feel like having something different, prepare sparkling water with ice, lemon and a few slices of fresh ginger.

It is refreshing, contains almost no energy and can replace sugary soft drinks, slush drinks or cocktails.

Kombucha can be another option, but check the label because some varieties contain a considerable amount of residual sugar.

Choose lower-sugar versions and remember that even though kombucha is fermented, it should not replace water as your main drink.

Practical tip: look for a product containing less than 2.5 g of sugar per 100 ml.

5. Intermittent energy restriction: avoid continuous restriction

During prolonged energy restriction, the body activates conservation mechanisms: hunger increases, spontaneous movement decreases and muscle mass may be lost.

Signals such as leptin, which is related to satiety, may also decrease, while peripheral thyroid activity may fall slightly within the physiological range.

As a result, energy expenditure may decrease slightly more than expected from the amount of weight lost.

This phenomenon is known as adaptive thermogenesis and does not mean that your metabolism is “broken”.

It is a physiological response to a sustained reduction in energy availability.

Alternating energy-deficit periods with days or weeks at maintenance may reduce hunger, improve energy levels and make the plan easier to follow.

In some protocols, it may also help preserve performance, daily movement and part of energy expenditure, although this is not guaranteed.

These pauses are not “cheat days”. Energy needs are met without eating freely or compensating with excessive intake.

Protein, vegetables, fibre, quality carbohydrates and appropriate fat intake are still maintained.

The aim is not to trick the metabolism, but to avoid continuous restriction and make the process more sustainable.

What happens during prolonged energy restriction?

When a person consumes less energy for several weeks, the body may respond in the following ways:

• Body weight decreases, reducing the energy required to maintain it.
• Muscle mass may be lost.
• Spontaneous movement, or NEAT, may decrease.
• Hunger may increase.
• Signals such as leptin may decrease.
• Peripheral thyroid function may decrease slightly within the physiological range.
• Energy expenditure may fall slightly more than expected from the weight loss itself.

This last response is known as adaptive thermogenesis.

It does not mean the metabolism is “broken”. It is a conservation response to reduced energy availability.

What can an intermittent approach offer?

Introducing days or weeks at maintenance calories can provide both the body and the person with a break from the deficit.

It may potentially help to:

• Reduce hunger.
• Improve perceived energy.
• Maintain sports performance.
• Reduce irritability associated with restriction.
• Improve adherence.
• Preserve daily movement.
• Reduce part of the metabolic adaptation in some protocols.

It does not mean eating freely

A metabolic break is not a “cheat day” or a day of overeating.

The structure may look like this:

• Moderate deficit days: energy intake is slightly below requirements.
• Maintenance days: energy intake approximately matches requirements.

A weekly energy deficit may still exist if the goal is fat loss.

Fat loss requires an energy deficit, either by consuming fewer calories or by using more energy through movement. However, the deficit does not necessarily need to occur every single day; it can also be created across the week as a whole.

A maintenance day should still include:

• Adequate protein.
• Vegetables and fibre.
• Quality carbohydrates.
• Appropriate fat intake.
• No compensatory overeating or bingeing.

6. Supplements: which ones may make sense?

There is no supplement that can compensate for a sedentary summer.

No capsule can replace daily movement, strength training, rest, a structured diet or a well-planned energy deficit.

There is also no product capable of significantly “activating” a metabolism that receives too little sleep, loses muscle mass and remains sedentary for most of the day.

Supplements may be useful, but only when they:

• Address a specific need.
• Correct a deficiency.
• Improve adherence.
• Complement a nutritional intervention.
• Are appropriate for the person’s health status and medication.

The question should not be:

“Which supplement makes you lose weight?”

Instead, ask:

“Which specific obstacle do I need to solve?”

Let us look at some of the main options:

• Protein.
• Creatine.
• Magnesium.
• Omega-3.
• Psyllium.
• Vitamin D.
• Berberine.

Protein may make it easier to meet protein requirements and preserve muscle. Creatine may improve performance when combined with strength training.

Magnesium may be useful when intake is insufficient or a deficiency exists, while omega-3 may be appropriate when oily fish intake is low or there is a cardiometabolic indication.

None of them causes significant fat loss on its own.

Psyllium may support bowel regularity, satiety and cholesterol levels when fibre intake is low, provided it is taken with enough water.

Vitamin D should be supplemented when there is a deficiency or clinical indication. Taking more will not promote weight loss and excessive intake may be toxic.

Berberine may be useful in specific metabolic conditions, but it has pharmacological activity and may interact with medication.

It is therefore not a general weight-control supplement and should be considered with professional guidance.

1. Protein powder

Protein powder is not a fat burner. It is a practical tool for meeting protein requirements when doing so through food alone is difficult.

It may help to:

• Improve satiety.
• Preserve muscle mass during an energy deficit.
• Support recovery after training.
• Improve breakfasts or snacks that are low in protein.
• Meet protein needs during travel, holidays or less organised days.

It may be particularly useful for:

• People who do strength training.
• Women going through menopause.
• Older adults.
• Poorly planned vegetarian or vegan diets.
• People with a low appetite or difficulty organising their meals.

One serving may provide approximately 20–30 grams of protein, depending on the product.

It can be added to yoghurt, kefir, plant-based drinks, porridge or smoothies.

Protein powder does not cause weight loss. It helps preserve what you do not want to lose while reducing body fat.

2. Creatine monohydrate

Creatine is one of the most extensively studied supplements for improving performance during high-intensity exercise and supporting adaptations to strength training.

It may help to:

• Increase training capacity.
• Improve strength.
• Support the maintenance or development of lean mass.
• Preserve function during ageing.
• Support muscle health during menopause.

Its main metabolic benefit is indirect: it helps you train more effectively and protect muscle mass.

The standard option is creatine monohydrate, generally taken at a dose of 3–5 grams per day. A loading phase is not essential.

Does creatine cause weight gain?

Creatine may cause a small increase in body weight at first because more water is retained inside the muscle. This does not mean that body fat has increased.

It works especially well when combined with strength training. Without that training stimulus, its ability to improve body composition is much more limited.

In postmenopausal women, the combination of creatine and strength training shows promising results for lean mass and physical performance.

3. Magnesium

Magnesium is involved in many processes related to:

• Energy production.
• Muscle contraction and relaxation.
• Nervous system function.
• Glucose regulation.
• Protein synthesis.
• Sleep and rest.

However, this does not mean that magnesium supplementation speeds up metabolism.

It may be useful when dietary intake is insufficient, but it is not a weight-loss supplement.

It may support fluid balance, muscle function, rest and the maintenance of adequate energy levels.

The original article suggests magnesium bisglycinate or a formula combining bisglycinate, citrate and malate.

Magnesium may help support the energy needed to move and take care of yourself, but it does not automatically remove body fat.

4. Omega-3

Omega-3 fatty acids EPA and DHA may be useful for people who consume little oily fish.

They may contribute to:

• Reducing triglycerides at therapeutic doses.
• Supporting cardiovascular health.
• Participating in the regulation of inflammatory responses.

There is no solid evidence to recommend omega-3 supplements specifically for weight loss. They do not “melt” abdominal fat.

The required amount depends on the goal. Supplementing a diet low in oily fish is not the same as treating elevated triglycerides.

Omega-3 may improve the cardiometabolic context, but it does not replace an energy deficit or physical activity.

5. Psyllium

Psyllium is a soluble fibre that absorbs water and forms a gel in the intestine.

It may be useful when the diet does not provide enough fibre and may help to:

• Improve bowel regularity.
• Increase stool consistency.
• Support satiety.
• Moderate the post-meal glucose response.
• Modestly reduce LDL cholesterol.

Some studies show a reduction in hunger, but the results for weight loss are variable.

It should not be marketed as a weight-loss product.

It may be helpful during travel or changes in routine if constipation occurs.

Start with a small amount, increase it gradually and always take it with enough water.

Psyllium may also interfere with the absorption of medication, so it should be taken separately according to professional advice.

Before adding psyllium, consider whether you can increase fibre through vegetables, fruit, legumes, seeds and whole grains.

6. Vitamin D

Vitamin D is involved in:

• Bone health.
• Muscle function.
• Immune regulation.
• Calcium and phosphorus metabolism.

Low vitamin D levels are frequently associated with obesity and poorer metabolic health, but this does not prove that vitamin D deficiency causes weight gain.

Vitamin D supplementation does not produce significant fat loss in people who already have adequate levels.

Supplementation may make sense when:

• A deficiency or insufficiency is present.
• There is a medical indication.
• Sun exposure is limited.
• Other factors increase the risk of deficiency.

The dose should be individualised according to blood tests, sun exposure, diet and clinical circumstances.

More is not necessarily better, and excessive vitamin D intake may be toxic.

Vitamin D corrects a deficiency. It is not a weight-loss strategy.

7. Berberine: not for everyone

Berberine is a plant alkaloid with pharmacological activity.

It has been studied particularly in people with:

• Insulin resistance.
• Type 2 diabetes.
• Abnormal cholesterol or triglyceride levels.
• Polycystic ovary syndrome.
• Certain forms of metabolic syndrome.
• Some bacterial infections, such as those caused by Helicobacter pylori.

It may influence pathways related to glucose and lipid metabolism.

Some meta-analyses report small reductions in body weight or waist circumference, but study quality is inconsistent and the weight-loss effect is modest.

It is not “natural Ozempic” and should not be used to compensate for summer excesses.

It may also cause:

• Nausea.
• Abdominal pain.
• Constipation or diarrhoea.
• Excessively low blood glucose when combined with medication.
• Interactions with numerous medicines.

Berberine is a context-specific intervention that requires professional assessment.

So, which option should you choose?

Situation	Option that may be considered
Difficulty meeting protein needs during summer meals	Protein powder
Strength training and muscle preservation	Creatine
Insufficient intake of leafy green vegetables	Magnesium
Low intake of oily fish	Omega-3
Low fibre intake or constipation when away from home	Psyllium
Tendency towards low vitamin D levels or a clinical indication	Vitamin D
A specific glucose or metabolic disorder	Berberine, with professional supervision

The supplements that make the biggest “fat-burning” promises are often the ones with the weakest evidence.

Many combine caffeine, plant extracts and stimulants that may:

• Disrupt sleep.
• Increase anxiety.
• Raise heart rate.
• Cause digestive discomfort.
• Worsen the very factors that make weight regulation more difficult.

Save the money you would spend on fat burners for good-quality olive oil, oily fish or one extra day of holiday.

Because no supplement can match the metabolic return of:

• Muscle.
• Movement.
• Fibre.
• Rest.
• A way of eating you can actually maintain.

Enjoy summer without turning September into a punishment

Summer should not be a break from your health.

Nor should it be a prison.

Enjoy the ice cream.

The terraces.

Dinners with friends.

Your free time.

Just make sure September does not become a punishment for having enjoyed August.

Your metabolism does not need perfection. It needs consistency.