Ketogenic side effects

Is it typical to experience severe fatigue, muscle weakness and low grade fever after starting the Ketogenic plan?

My history: I have followed a very wholesome ( but low-fat) vegan plan for 15 years . Over time I have become too reliant on carbs for fuel - and it's affected my blood sugar levels.

I cycle 50+ miles a week, do organic gardening and make 99% of my food from "scratch." I became gluten free a year ago and introduced fermented foods 9 months ago.

I keep taking my diet up a notch for maximum health and wellness. I am rarely sick... so this fever and weakness is a real concern.

It's been nearly a week and although the fever broke after four days, I still feel rundown.

ALL input welcome.

Best Answer


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    Going into ketosis can result in a pretty significant loss of lean muscle tissue, especially if you aren't engaging in regular resistance activity. I would also be concerned that if you are losing lean tissue, your immune system is being compromised.

    It's essential for you to be eating enough calories and to consume adequate protein to meet lean tissue demands (I wouldn't go less than 0.8 g per kg of body weight). You may also wish to connect with a dietitian in your area who is familiar with keto diets.

    Kind regards,

    Susan Macfarlane, MScA, RD
    Registered Dietitian Nutritionist
    As always, any and all postings here are covered by our T&Cs:

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    edited February 2018

    Thanks Susan. I appreciate your input. I am definitely not losing lean muscle though. Maybe I was just fighting off that flu bug others have been talking about. I am feeling much better today. Cycled 25 miles with no muscle weakness.

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    Yes, there are definitely side effects to starting a ketogenic plan and mine lasted a couple weeks total. I have since recognized that a high fat diet regimen gives mitochondria time to clean house. This begins with a glut of dead cells hitting the bloodstream. That can result in a fever (from what I have learned from other health studies) which is what made this transition period so miserable for me. This process is called autophagy if I understand the term correctly. While I had the low grade fever, I also experienced chest congestion. Maybe my lungs had the greatest toxic load and need for cleansing. This makes sense since I grew up around many smokers and was exposed to crop dusting chemicals.

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