Can keto cause severe lasting weakness?


Why isn’t keto working for me? Do I need more carbs in the morning to feel less fatigue? Are artificial sweeteners ok in moderation?

Get the answers to these and other questions in this week’s Q&A with me:

Why isn’t this working?

Age 55, 213 pounds (97 kilos). I have been on the two-week challenge, started no carbs or sugar the week prior. Going on three weeks, and my weight fluctuates from 213 to 206 (93 kilos) and now 211 pounds (96 kilos).

I am sad, depressed, breaking out in a rash on my arms nightly, irritable and nothing has been positive except for the delicious recipes. I even tried working out with video at home.

I am really discouraged and just feel like I am blowing up in proportion.


Hi Karen!

Sorry to hear about your struggles. Weight loss can be a challenge, not least for women after 40.

Perhaps this can be useful:

Top 10 tips to lose weight on low carb or keto for women 40+

Andreas Eenfeldt

Ongoing fatigue

I have been eating low carb for two months. Weight is normal and stable. I feel fatigue, especially in the mornings even after eating. Sometimes fatigue is worse after eating.

I’ve tried adding sodium, bone broth, more fat, more protein. Nothing is working well. A dietitian told me to eat more carbs in the morning: sweet potato or oatmeal. What do you think?




You could certainly try it. Also, and perhaps obviously, make sure you get enough quality sleep. And if nothing seems to work, perhaps see a doctor for some routine tests.

Andreas Eenfeldt

Are artificial sweeteners ok in moderation?

I specifically love to drink a single Diet Coke per day. Is this habit slowing down my results?


It might, although this is controversial:

Artificial sweeteners

It’s not likely to be a major factor.

Andreas Eenfeldt

Can keto cause severe lasting weakness?

Since being on keto since January 2017, I have lost a lot of weight and my health has improved except for incredible weakness specifically in my shoulders. I have to rest when climbing stairs as I get winded and suddenly feel like I’ve climbed many more stairs than I have.

The weakness comes on suddenly and goes away after a brief rest. Have you ever heard of this being a rare side effect of this diet? I’ve had so many tests and they can’t find anything else wrong with me to explain this.


Hi Diana!

Have you tested extra water and salt, e.g. a cup of bouillon a day? Weakness is a common effect of a lack of salt, and that can happen more easily on a keto diet.

As long as your blood pressure is under control, trying some extra salt should be very safe:

Low-carb and keto side effects & how to cure them

Andreas Eenfeldt


Keto for beginners

Intermittent fasting for beginners

How to lose weight

More questions and answers

Many more questions and answers:

Low-carb Q&A

Read all earlier questions and answers – and ask your own! – here:


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