Weight loss and breastfeeding: the truth about calories

This is a question that many new mothers ask themselves after giving birth: does breastfeeding really help you lose weight? Between social pressures to get your "pre-pregnancy body" back and the actual physiological changes that occur, understanding the link between breastfeeding and weight loss is essential for a peaceful postpartum period.

At 23 Mai Paris, we support mothers with kindness. Spoiler alert: it's not an exact science, but a question of metabolic balance and overall well-being. Here's the truth about calories and breastfeeding.

The caloric mechanism of lactation

Producing breast milk requires considerable energy from your body. On average, the body expends between 400 and 500 calories per day just for lactation. To give you an idea, this is equivalent to:

• A 45-minute swimming session
• 1 hour of brisk walking
• 30 minutes of moderate running

On paper, it looks promising! In theory, this extra energy expenditure should promote weight loss.

But there is a "but"...

This energy expenditure is often accompanied by a natural increase in appetite. Your brain sends hunger signals to compensate for this loss of energy. This is a perfectly normal survival mechanism: your body wants to ensure that you have enough resources to feed your baby.

The result: some mothers naturally eat more and don't lose weight, while others slim down effortlessly. It all depends on your individual metabolism.

Why weight loss can stall (or not happen)

If you are breastfeeding and your weight isn't changing, don't feel guilty. Several factors influence the scales, beyond calories burned:

1. Hormones

Prolactin, the hormone responsible for milk production, can promote fat storage in some women. This is a protective mechanism: your body builds up reserves to ensure milk production.

Some mothers only start to lose weight after weaning, when their hormones return to normal. This is perfectly normal.

2. Lack of sleep

Fatigue increases the production of cortisol (the stress hormone), which:

• Promotes fat storage, especially around the belly
• Increases cravings for sugar and fat
• Slows down metabolism

With a newborn baby waking you up several times a night, sleep deprivation is almost inevitable. And it has a real impact on your weight.

To better manage nights, check out our article Nighttime breastfeeding: tips for surviving nighttime feedings.

3. Stress and mental load

Becoming a mother is life-changing. Chronic stress, even if unconscious, maintains high cortisol levels, which slows down weight loss.

4. Hydration

Water is essential for producing milk (breast milk is 87% water!). But staying well hydrated also helps regulate your metabolism and prevent water retention. Aim for 2 to 2.5 liters per day.

5. Genetics and individual metabolism

Some women naturally lose weight while breastfeeding, others do not. It is neither a question of willpower nor failure. Every body is different.

The truth that nobody tells you

Here's what we often forget to tell new moms:

• Nine months to gain, nine months (or more) to lose: your body took nine months to transform, so it's normal that it will take at least as long to regain its balance.

• Weight isn't everything: body composition changes. You can weigh the same but have a different figure.

• Some mothers only lose weight after weaning, which is perfectly normal. Breastfeeding hormones can cause you to retain a few extra pounds.

• Social pressure is toxic: celebrities who get back into shape in six weeks have coaches, chefs, nannies... That's not the reality for most moms.

Feeling beautiful during the postpartum transition

Rather than focusing solely on the number displayed on the scale, it is essential to reclaim your body as it is today.

At 23 Mai Paris, we believe that nursing wear plays a major psychological role. Wearing a Breastfeeding dress or a well-cut breastfeeding sweatshirt that fits well makes you feel valued, no matter where you are in your journey.

What really matters:

• Feel comfortable in your clothes. To find pieces that flatter you, check out our article Stylish nursing outfits: 5 tips for staying chic.
• Having the energy to enjoy your baby
• Taking care of your mental health
• Don't compare yourself to others

Your body has accomplished something extraordinary. It deserves kindness, not punishment.

Tips for a healthy balance

Do not try to follow a restrictive diet while breastfeeding. This could affect your milk production and your energy levels (which are already under strain).

What to prioritize:

• High-quality protein: eggs, chicken, fish, legumes (for satiety and muscle mass)
• Good fatty acids: salmon, nuts, olive oil, avocado (essential for you and your baby's development)
• Whole grains: brown rice, quinoa, whole wheat bread (for stable energy)
• Fruits and vegetables: vitamins and fiber
• Hydration: water, herbal teas, soups

For more nutrition tips, check out our article Food and breastfeeding: 5 tips for staying in shape.

What to avoid:

• Diets with less than 1,800 calories per day
• Skipping meals
• Weight loss products not approved during breastfeeding
• Weigh yourself every day (normal fluctuations)

The goal is to feed your baby while taking care of your energy levels. Breastfeeding and weight loss should be done at your body's pace, without excessive pressure.

Conclusion

Breastfeeding can help you lose weight due to the calories burned, but this is not guaranteed for everyone. Hormones, sleep, stress, genetics: many factors come into play.

The most important thing? Take good care of yourself. Eat a balanced diet, stay hydrated, sleep when you can, and wear clothes that make you feel beautiful.

At 23 Mai Paris, we support mothers with comfortable and stylish nursing clothes , so you can get through this period feeling good, whatever stage you're at.

Browse our collection of nursing clothes and find the pieces that will make you feel beautiful at every stage.