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When to avoid low-carb diet


Fatigue, constipation or slow metabolism could be the signs that you need to increase your daily carbohydrate intake.

These symptoms are familiar for ketogenic dieters, or any other low-carbohydrate diet. Our daily activities, body condition and life stages differ, thus one might need higher daily carbohydrate intake than others.

Who should avoid a low-carb diet?

When people consume more carbohydrate than they need at the time, the body stores some of these carbohydrate within cells and converts the rest to fat. Carbohydrate and fat are essential sources of energy for our body. Not only that, carbohydrate also serves as great source of antioxidants and micronutrients.

There are many conditions when a low-carb diet is doing more harm than good. You might need to increase your daily carbohydrate intake if you are in one of these categories.


Pregnant and Lactating Women 

Optimal nutrition and carbohydrate intake are important during preconception period, pregnancy, and lactation. Adequate macronutrient is needed for fetal brain development and growth. Not only that, protein consumption is limited during pregnancy and when you cut off carbohydrate, you can’t help but to increase your protein intake. The limit of protein consumption is 20-25% of energy for various physiological reasons.

Research has linked a high-protein, low-carbohydrate diet during pregnancy to increased cortisol in offspring. (1) Ketogenic diet during pregnancy also reduces the size of the child’s critical brain regions and has other effects on their brain’s structure.(2)

The harmful effects of low-carb diets on infants are not limited to preconception and pregnancy; a low-carb diet during lactation may alter milk production and composition and reduce infant growth.(3)



Limiting carbohydrate could put your kids at risk for developing deficiencies later in life. As the body’s preferred energy source, experts recommend about half of the calories children consume come from carbohydrate. But this can be tricky as carbohydrate is everywhere–cakes, cookies, candy, and sodas–but we’re talking about good source of carbohydrate such as whole grains, fresh fruits and dairy. Fiber, calcium and vitamin D  are among of many important nutrients which children lack of, and carbohydrate-rich food are good resource for these key nutrients.

It all comes down to getting into the habit of eating healthier choices.



While there are many well-planned low-carb diets for athletes, not all of these are actually good for health. Each athletes has unique needs, and low-carb diets can affects their performance. Therefore, it is advised to test and see if certain diet methods could affect their athletic ability.

One of the signs is that if you’ve been on a low-carb diet for a long period of time but your exercise has been suffering, your weight is stagnant–or you've even been putting on weight–, and you take more time to recover, then maybe it is time to reevaluate if you can handle a low-carb diet combined with intense physical work-out.

There are many surprising results of following a more moderate carbohydrate intake. Many people found after switching their diet approach, that their endurance and energy have significantly increased. Many also found that they were able to shed stubborn body fat.

"Maintaining a macronutrient balance at every meal/snack that contains 45-65% calories from carbohydrate, 15-30% calories from protein and 15-30% calories from fat will help to stabilize blood sugar, insulin and serotonin levels.”
— Dr. Rick Kattouf

Keep in mind that every athlete has different needs, what works for one person might not work for you. Get help if needed, and pay attention to how your diet affects your performance and well-being.


People with Hypothyroidism

Carbohydrate affects thyroid function because insulin is needed to convert T4 hormone into the active T3 hormone, and insulin is generally quite low in every low-carb diet. Needless to say, if you start developing hypothyroid symptoms on your low-carb diet, this might be the sign that you need to increase your carbohydrate intake.


Hypothyroid symptoms:

  • Cold hands and feet
  • Thinning hair
  • Constipation
  • Fatigue


People with HPA Axis Dysregulation

HPA or Hypothalamic Pituitary Adrenal, is our central stress response system. This axis is very dynamically intertwined with central nervous system, and also helps to regulate our immune system function, mood, and energy usage. HPA dysregulation is triggered by chronic stress which affects the body’s resilience and metabolic reserve and high cortisol is commonly found in people with HPA dysregulation.

Cortisol plays a role in converting protein to glucose when your carb supply is low, which is why there is concern that a low-carb diets might play a role in elevating cortisol levels. By slightly increasing carbohydrate intakes, it may be helpful to HPA axis dysfunction treatment.

¹ Price, Weston A. MS., D.D.S., F.A.G.D. (1939). Nutrition and
Physical Degeneration. Medical Book Department of Harper & Brothers.
² Stein, Aryeh D. (2009). Maternal Exposure to the Dutch Famine Before Conception and During Pregnancy: quality of life and depressive symptoms in adult offspring. Epidemiology.
³ Koski KG, Hill FW, Lönnerdal B. (1990). Altered Lactational Performance in Rats Fed Low Carbohydrate Diets and Its Effect on Growth of Neonatal Rat Pups. US National Library of Medicine National Institutes of Health.


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