Bone Broth During a Fast: What the Evidence Says

Fasting while maintaining electrolyte balance presents unique challenges. The ketogenic diet often incorporates fasting windows, raising questions about what consumables maintain metabolic benefits. Bone broth, rich in minerals and collagen, sits at the centre of this debate.

Does Bone Broth Break a Fast?

Pure fasting means consuming nothing with caloric content. Bone broth typically contains 30-50 kcal per 250 ml from protein and trace fats. Research suggests minimal protein intake under 50 kcal may not significantly impact insulin response (Sumithran et al., 2013). For those prioritising autophagy, any calorie intake could theoretically reduce benefits.

Electrolyte Considerations

UK tap water contains negligible magnesium and potassium. Bone broth provides these electrolytes alongside sodium, crucial during extended fasts. A study on ketogenic diets noted improved hydration markers with adequate electrolyte intake (Volek et al., 2008). In winter months, warm broth also helps maintain core temperature.

What This Means in Practice

Tesco sells 500 ml cartons of organic bone broth for £2.80. During a 16:8 fast, consuming 100-200 ml provides electrolytes without substantial calories. Those doing prolonged fasts may prefer homemade versions with added sea salt for sodium. The NHS recommends consulting a GP before fasts exceeding 24 hours.

Frequently Asked Questions

Will bone broth kick me out of ketosis?

Unlikely in modest quantities. The minimal carbohydrates in bone broth (under 2g per serving) shouldn’t disrupt ketosis for most individuals.

Is shop-bought broth as good as homemade?

Homemade allows control over ingredients, but UK supermarket options like Waitrose Cooks’ Ingredients Bone Broth provide convenience. Check labels for added sugars or starches.

How does bone broth compare to electrolyte supplements?

Broth offers natural electrolytes alongside collagen. Supplements provide precise mineral doses but lack the gut-supporting amino acids found in the best keto electrolyte sources.

The Bottom Line

Bone broth during fasting involves trade-offs. It provides valuable electrolytes and warmth during UK winters but may slightly reduce fasting’s cellular benefits. For those struggling with hydration or fasting fatigue, 100-200 ml of broth presents a reasonable compromise. If you’d rather not do the macro maths yourself, the Keto Dieting app does it for you on Google Play and the App Store.

References

1. Sumithran P, Prendergast LA, Delbridge E, et al. (2013). Ketosis and appetite-mediating nutrients and hormones after weight loss. European Journal of Clinical Nutrition. https://doi.org/10.1038/ejcn.2013.90
2. Volek JS, Phinney SD, Forsythe CE, et al. (2008). Carbohydrate restriction has a more favorable impact on the metabolic syndrome than a low fat diet. Lipids. https://doi.org/10.1007/s11745-008-3274-2