Is the Keto Diet Causing Your Fatigue and Brain Fog?

Is the Keto Diet Causing Your Fatigue and Brain Fog?

The ketogenic (keto) diet has gained a reputation for rapid weight loss and improved mental clarity. But many people report feeling sluggish, moody, and mentally foggy after a few weeks on this high-fat, low-carb plan. If that sounds familiar, you’re not alone—and your diet may be the problem.

Here’s what you need to know about the hidden side effects of keto, and why a more balanced approach may be better for your long-term health.

1. Keto Flu and Adrenal Fatigue

When you drastically cut carbohydrates, your body shifts into ketosis—a process that requires adaptation. During this phase, many people experience “keto flu”:

• 頭痛
• 疲勞
• Irritability
• Brain fog

This stress on your system can overwork the adrenal glands, leading to long-term fatigue and hormonal imbalance (Cox et al., 2020).

2. Thyroid Dysfunction

Low-carb diets like keto can reduce levels of active thyroid hormone (T3), slowing metabolism and energy production. This is especially problematic for women, who are more sensitive to thyroid fluctuations.

3. Gut Health Disruption

By eliminating fiber-rich foods like fruits, legumes, and whole grains, keto can starve your beneficial gut bacteria. Over time, this can:

• Increase gut permeability (leaky gut)
• Weaken the immune system
• Promote inflammation

(David et al., 2014)

4. Brain Fog and Mood Swings

The brain relies on glucose as its primary fuel. While it can adapt to using ketones, many people experience reduced clarity, difficulty focusing, and emotional volatility—especially when electrolytes are imbalanced or calories are too low.

5. Long-Term Health Risks

High-fat keto diets often emphasize animal products, which can increase levels of saturated fat, TMAO, and inflammatory markers. These are linked to:

• Heart disease (Koeth et al., 2013)
• Fatty liver disease (Jou et al., 2008)
• Hormonal disruptions

A Better Way: The ASTR Diet

Created by Dr. Joseph Jacobs, the ASTR Diet offers a safer, more sustainable path to healing. It includes:

• Balanced macronutrients—not extreme carb restriction
• Organic vegetables and fiber-rich fruits
• Clean proteins like wild fish and legumes
• Healthy fats from olives, avocado, and seeds
• Intermittent fasting for metabolic support

This approach helps eliminate fatigue, brain fog, and hormonal imbalance by nourishing the whole body—not stressing it.

Find Relief the Natural Way

If you’ve hit a wall with keto—mentally, physically, or emotionally—it’s not your fault. Your body is asking for balance.

Discover the full ASTR Diet approach in Eat to Heal by Dr. Joseph Jacobs: Available on Amazon

參考：

• Cox MM, et al. (2020). Biochemical and physiological effects of ketogenic diets. Annual Review of Nutrition.
• David LA, et al. (2014). Diet rapidly and reproducibly alters the human gut microbiome. Nature.
• Koeth RA, et al. (2013). Intestinal microbiota metabolism of l-carnitine and cardiovascular risk. N Engl J Med.
• Jou J, et al. (2008). Pathogenesis of nonalcoholic fatty liver disease. Nat Clin Pract Gastroenterol Hepatol.1