Carb Balance: Eating Too Few Carbs On Keto Diet

The keto diet has gained popularity for its ability to aid weight loss. However, it is a very low-carb diet, and eating too few carbs can have some negative consequences. While it can help you lose weight in the short term, it is important to be aware of the potential drawbacks. Carbohydrates are the body's primary source of fuel, and slashing your intake can lead to reduced energy levels, difficulty concentrating, constipation, weight gain, and nutrient deficiencies. Additionally, very low-carb diets can lead to high cholesterol and an increased risk of heart disease. Therefore, it is crucial to be well-informed about the potential risks before embarking on a keto diet.

Tiredness and fatigue

Carbohydrates are the body's primary source of fuel. Slashing your intake can, therefore, have a significant impact on your energy levels. Carbs are converted to energy more efficiently than protein or fat, so it is normal to feel tired throughout the day when eating a low-carb diet.

Weakness and fatigue, sometimes called the "keto flu", are common side effects of a low-carb diet. According to a 2020 study in Frontiers in Nutrition, you may also experience difficulty concentrating at work, and feel grouchier than normal.

The 2020-2025 Dietary Guidelines for Americans advise getting 45-65% of our daily calories from carbs. Opting for 40% or less can have a major impact on the way your body functions.

Lisa Valente, M.S., R.D. says:

> "Since lots of people think about carbs in terms of grams, anything lower than 100 grams daily is pretty low. And since carbs have 4 calories per gram, that would be 400 calories, or only 20% of your daily calories on a 2,000-calorie diet."

If you are feeling tired, it may be worth upping your carb intake a little to ensure you have the energy to get through each day.

Bloating

The keto diet can sometimes cause bloating, which can be uncomfortable and make you look and feel more swollen or puffy than usual. This is often caused by an increase in water retention, which can be a side effect of the diet. When you reduce your carbohydrate intake, your body starts to use up its stored glycogen, and with each gram of glycogen, your body also stores water. As your body burns through its glycogen stores, it will also release this water, leading to a reduction in water retention and a decrease in bloating.

However, if you are experiencing bloating on the keto diet, there are several things you can do to alleviate the discomfort. Firstly, make sure you are staying adequately hydrated by drinking enough water throughout the day. Sometimes, counterintuitively, water retention can be caused by dehydration, so ensuring you are well-hydrated can help flush out excess fluids and reduce bloating.

Another way to combat bloating is to increase your fibre intake. The keto diet can be low in fibre, especially if you are not consuming enough non-starchy vegetables and other fibre-rich foods. Aim to include a variety of keto-friendly high-fibre foods in your diet, such as leafy greens, broccoli, avocados, nuts, and seeds. Additionally, consider taking a fibre supplement to ensure you are meeting your daily fibre needs.

Certain keto-friendly foods can also cause bloating in some individuals. Common culprits include dairy products, sweeteners, and sugar alcohols. If you suspect a particular food is causing your bloating, try eliminating it from your diet for a period, and then slowly reintroduce it to identify any triggers. Keeping a food diary can help you track and identify any specific foods or ingredients that may cause bloating.

Lastly, remember that stress and poor digestion can contribute to bloating. Practise mindful eating, and incorporate relaxation techniques such as deep breathing or meditation to improve digestion and reduce bloating. Regular physical activity can also help reduce water retention and improve digestion.

Lack of concentration

A low-carb diet can impair your concentration and make you feel grouchier than usual. This is because carbohydrates are the primary source of fuel for our bodies. Slashing your intake can, therefore, have a major impact on your energy levels. Carbs are converted to energy more efficiently than protein or fat, so you may start to feel sluggish throughout the day on a low-carb diet.

According to a 2023 review in Physical Activity and Nutrition, this can also negatively impact your workouts, as you may not feel like you have the strength to push through a sweat session as you used to.

High-quality carbs like sweet potatoes, whole-wheat bread, berries, and quinoa are essential for not only giving you the energy to get through your workday but their protein-fibre combination also helps to lower blood sugar spikes and prevent you from crashing.

Instead of reaching for another cup of coffee in the afternoon, it might be worth strategizing your carbohydrate intake to allow for a high-fibre afternoon snack.

The 2020-2025 Dietary Guidelines for Americans advise getting 45-65% of our daily calories from carbs. Opting for 40% or less can have a major impact on the way your body functions. Eating too few carbs could be consequential.

Weight gain

While a low-carb diet may help you lose weight in the short term, it can also lead to weight gain in the long run. Here's how:

The Body's Reaction to Low Carb Intake

When you drastically reduce your carbohydrate intake, your body may react by trying to produce its own usable glucose from protein or fat. As this continues, your body may start to store this sugar as fat to "prevent starvation". This is because the brain doesn't differentiate between true starvation and a deliberate reduction in calories or carbohydrates.

Cravings and Binging

Any restrictive diet is likely to lead to cravings, which can result in binging. After stopping a low-carb diet, any weight lost is likely to return, and you may even gain more weight than before.

Lack of Sustainable Changes

As with any diet, it is important to make realistic, sustainable changes to maintain weight loss. If you are feeling too tired to exercise due to a low-carb diet, it will likely cause the scale to go up and won't be sustainable in the long term.

Nutrient Deficiencies

A low-carb diet can put you at risk of nutrient deficiencies, which can weaken your immune system. Many necessary vitamins, minerals, and antioxidants are found in carbohydrate-rich foods, such as whole grains, fruits, and vegetables, which are often restricted on low-carb diets.

High-Fat Content

Very low-carb diets are often high in fat. While your triglycerides and HDL ("good") cholesterol levels may improve, there is also a risk of an increase in LDL, or "bad" cholesterol, which can lead to heart disease. It is important to focus on healthy fats, such as those found in avocados, olives, and nuts.

Difficulty in Maintaining the Diet

The keto diet, for example, requires a very low carbohydrate intake, usually less than 50 grams per day, to achieve ketosis. This leaves you with limited carb options, mainly vegetables and small amounts of berries. Maintaining such a restrictive diet can be challenging, and any deviation from it may lead to weight gain.

Nutrient deficiencies

Eating too few carbs on a keto diet can lead to nutrient deficiencies, which can have various negative impacts on your health and well-being. Here are some of the key consequences:

Energy and Concentration

Carbohydrates are the body's primary source of fuel for metabolism, energy, and digestion. Slashing your carb intake can significantly impact your energy levels, making you feel constantly tired and sluggish. This can also impair your concentration, making it difficult to focus at work or on other tasks.

Weight Gain

Ironically, very low-carb diets can lead to weight gain over time. This happens because your body may start producing its own glucose from protein or fat, and then store this sugar as fat to "prevent starvation." This can cause the number on the scale to creep up, even if your body composition is improving due to muscle gain.

Hunger and Appetite

Complex carbohydrates help regulate hunger and fullness cues, and their absence can disrupt these signals. This may lead to increased hunger and a higher risk of cravings and binge eating. Additionally, the absence of fibre in a low-carb diet can cause constipation and other gastrointestinal issues, further impacting your appetite and overall health.

Nutrient Deficits

By cutting out carbs, you're not just reducing your sugar and grain intake; you're also eliminating fruits, whole grains, and many vegetables that deliver essential fibre, vitamins, minerals, and antioxidants. This can weaken your immune system and make you more susceptible to illness.

Heart Health

Very low-carb diets are typically high in fat, and if you're not careful about the types of fat you consume, you may increase your risk of heart disease. It's important to focus on healthy fats like those found in avocados, olives, and nuts, and limit your intake of saturated fats.

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