Is Shiitake Mushroom Keto?
Shiitake Mushroom is not keto-friendly because it is high in carbs. It may kick you out of ketosis even with a small serving size.
Too Much Carbs!
Shiitake Mushroom should be avoided on keto because it is very high in net carbs (12.29g of net carbs per 100g serving).
It is important to limit your net carb consumption to 20g - 30g per day to stay in ketosis. You can calculate your ideal daily net carb allowance by using this keto macros calculator.
As an alternative, you may look for other types of mushrooms that are low in net carbs.
Low in Fats
Shiitake Mushroom is both high in carbs and low in fats, which are the exact opposite of the macros required on a keto diet.
The ideal macronutrient ratio for keto is 70% fat, 20-25% protein, and 5-10% carbs. This means the majority of your foods should be both low in carbs and high in fats.