Diet for women: the 30-calorie rule

Melanie Ramos 9 min. of reading Women's Special Leave a comment

Article exclusively for women. We bring you a special diet: the 30-calorie rule.

If I got a euro every time I hear “there are no articles about diets for sporty girls”, you’d probably be reading the new owner of HSN or even with the leftovers I’d treat myself to some Inditex shopping.

It’s true that most articles online are aimed at men, and what little you find for women boils down to “get rid of cellulite with this detox diet”.

Still, it’s worth remembering that this blog already has several of my articles about women’s diets that:

Focus on improving performance,
Fat loss, or
How it affects the hormonal side of the process.

In today’s article, I’ll focus on talking, or better yet repeating, how restrictive food diets become the worst tool for women.

Common Mistake: restricting calories to the max

When a girl decides to improve her body composition, or in other words, lose body fat while maintaining muscle mass, she restricts her diet

To do this, she cuts out most carbohydrates (or even fats), eating only lettuce, cucumber, a piece of fruit like an apple, and some processed stuff like turkey breast, thinking it’s a perfect food because it’s low in fat.

If we look at the calorie content of a cucumber, it’s no more than 20-30 Kcal per 100 grams, lettuce provides about 15-20 Kcal, or even other veggies like zucchini about 25-30 Kcal.

Putting aside the importance of fats and proteins and focusing purely on calorie value, we’ll see that the TOTAL intake for a day doesn’t go beyond 800-1000 Kcal. This causes a big amount of weight loss, since muscle tissue, glycogen, and water will be lost, even losing 2-3 Kg without counting fat loss.

That’s why these diets have become so popular among women “lose 3 kg in a few days? Where do I sign?”

What is the female athlete triad?

What many women don’t know is that following these restrictive diets can turn them into potential slaves of the famous female athlete triad.

We could say the triad is a series of harmful effects caused by a disruption in calorie intake. To sum it up, it boils down to 3:

Lack of energy.
Altered or lost menstruation.
Poor bone health or even osteoporosis.

Maybe you’re thinking you suffer from this or know a girl close to you with these symptoms (especially the first two)

And believe me, it’s no surprise, since up to 70% of female athletes have lost their menstruation, which is quite shocking when the percentage drops to 2-3% in regular women^[1],[2],[3]

Which group of women are more prone to the triad?

We find women training at high intensity, as well as those aiming for body fat below 15-16% (remember essential fat in women is around 10-12%).

Female athlete triad. Restrictive diets cause poor bone health, lack of energy, and menstrual cycle disruption. Image adapted from femaleathletetriad.org

Causes of the Triad

If we look for what causes the loss or alteration in the menstrual cycle, it’s the disruption in the “pulses” of LH (Luteinizing Hormone) plus an imbalance in the hypothalamic-pituitary-adrenal axis (known as HPA).

Along with this, we can find low levels of estrogens and leptin, which if you remember from my article about the menstrual cycle, act on our hypothalamus reducing hunger sensation. Also, leptin affects the release of gonadotropins (which includes LH mentioned above).

Though the previous paragraph might sound weird, it’s easy to understand:

If your calorie intake is low, your body fat drops releasing less leptin and your body “creates” hunger signals to increase calorie intake and recover the fat you lost. See? Much easier to get now!

How to fix the problem

It’s no news that to lose fat you need to create a calorie deficit, or in other words, burn more calories than you consume…

We can achieve this in two ways:

Either reduce the calories you eat.
Or increase the amount of exercise you do.

Now, without considering scientific studies or expert opinions, be honest: what do you think is better for your body, cutting nutrients or upping your exercise?

The answer is obvious:

Your body will respond way better by increasing calories while creating the energy deficit through physical exercise (whether intense or moderate)

When sessions last over 90 minutes or exercise intensity is above 70% VO2max, alterations occur in the HPA axis we mentioned earlier, releasing more cortisol or even catecholamines.

Don’t get me wrong, too much of anything is bad, even exercise

However, as with everything, it depends on the person’s fitness level, since some studies show trained athletes respond differently to “stress” than sedentary people or beginners, so trained people handle training stress better

Deficit through diet or training

Now, does creating a deficit through training have the same impact on women as through diet?

This question was asked by Loucks AB’s research group^[8], who put a group of women through physical training + moderate calorie diet versus a group creating a deficit with a very restrictive diet.

Later, results were compared with women on a moderate calorie diet without exercise

Results

The results were quite interesting:

Women doing high-intensity training DID NOT alter luteinizing hormone (LH) release.
Which DID happen in the low-calorie diet group.

This is important because some animal studies show that altered LH release strongly activates the HPA axis, releasing more cortisol.

To give you an idea, that’s a 100-200% increase, while exercise might raise cortisol levels by 10%^[9], though as always, individual differences are big.

As you can see, the key is NOT cutting calories in your diet, but increasing them according to your training

Who would’ve thought what you’ve been doing for years wasn’t right? Now, many of you are wondering how many calories you should eat to avoid these problems. That’s where my 30 Kcal rule comes in.

30 Kcal rule

The minimum intake you should have is 30 Kcal per kg of lean body mass / day.

That means if a girl weighs 60 Kg and after subtracting body fat she has 44 Kg lean mass, multiply 30 by 44, giving 1320 Kcal. These are the calories you must consume at LEAST to avoid entering the trouble zone.

Obviously, you should adjust calories to your training, so the actual amount you need is a bit higher

Conclusions

To sum up, we can simplify to:

Cutting out foods is NOT the best way to lose fat.
Very low-calorie diets cause hormonal disruption, leading to effects like amenorrhea, fatigue, or higher fracture risk.
Exercise is a stressor, but if done in a controlled way with proper calorie intake, its benefits help improve body composition.
To avoid problems, stick to the 30-calorie rule. Eat plenty of protein, around 2-2.5 g if hunger is high, fiber-rich foods like veggies, fruits, or even legumes. Base your diet on fiber, fat, and protein for your goal.

Just because your diet is based on the above doesn’t mean you should cut out carbohydrates

One option is to have 1-2 REFEEDs or high-carb days per week, including cereals, potatoes, tubers, or even small amounts of foods outside the diet (flexible dieting)

Hope this helps you, and little by little you reach your goal. Big hugs!