The missing carbohydrate in sports nutrition

Nondigestible fermentable carbohydrates (NFCs), are often called prebiotics. Prebiotics are dietary fibre that resists digestion in the upper gastrointestinal tract. Instead, they journey to the colon, where they become nourishment for beneficial gut bacteria. This fermentation process produces short-chain fatty acids (SCFAs), pivotal in maintaining gut integrity and overall health as outlined in our recent article.

Benefits of nondigestible fermentable carbohydrates in sports nutrition and gut health

The fermentation of nondigestible carbohydrates leads to several health benefits:

• Enhanced Digestion: SCFAs, such as butyrate, fuel the cells lining the colon, promoting efficient nutrient absorption and a robust gut barrier.
• Balanced Microbiome: Feeding beneficial bacteria helps maintain diversity, stability and a harmonious gut environment, preventing the overgrowth of harmful microbes.
• Reduced Inflammation: SCFAs possess anti-inflammatory properties, which can alleviate symptoms of gastrointestinal disorders such as irritable bowel syndrome (IBS), affecting 30% of the Australian population.
• Reduce symptoms: Fibre can significantly reduce gastrointestinal distress, such as constipation and bloating. Athletes often subject their bodies to intense physical stress, which can inadvertently impact gut health. High-protein diets, common among athletes, may alter gut microbiota composition, leading to increased production of proteolytic metabolites. This shift can exacerbate gastrointestinal distress during exercise, potentially impairing performance and recovery. Incorporating nondigestible fermentable carbohydrates can counteract these effects by fostering a more favourable gut environment.
• Enhanced mineral absorption. Undigestible carbohydrates, such as inulin and mannitol, can improve the absorption and bioavailability of essential minerals, including magnesium, calcium, zinc and iron.  To ensure you’re getting enough iron, include iron-rich snacks and recipes like the ones we prepared for you in our Iron Rich Snacks e-recipe book.

Incorporating Beneficial Carbohydrates into Your Diet

To harness the gut health benefits of nondigestible fermentable carbohydrates, consider the following dietary additions:

• Whole Grains: Oats, quinoa, and brown rice are rich in dietary fibre.
• Legumes: Chickpeas, lentils, and beans provide substantial fibre and resistant starch, supporting gut bacteria.
• Fruits and Vegetables: Bananas, asparagus, and garlic contain inulin and other prebiotic fibres. Inulin is also found in chicory root, Jerusalem artichoke, onion, leeks, burdock root, wheat and wheat bran. Mannitol is in mushrooms, cauliflower, celery, snow peas, butternut squash, sweet potato, apples, watermelon, cabbage, pumpkin, Brussels sprouts and peaches.
• Psyllium husk can be taken with water for added fibre.
• Resistant Starch-Rich Foods: Cooling cooked starchy foods like potatoes and rice increases their resistant starch content, therefore benefiting gut health.

Practical Tips

• Gradual Introduction: Slowly increase fibre intake to allow your gut to adapt, minimising potential discomfort. Research suggests that 30 grams of fibre daily is recommended to provide gut health benefits.
• Stay Hydrated: Adequate water consumption aids in the digestion and fermentation of fibres.

About the Author:

Kate Smyth provides sports naturopathy and nutrition advice and is a female-centric running coach. She founded the Athlete Sanctuary- a holistic healthcare clinic for athletes of all levels and sporting codes. She has been involved in sports for many decades and competed for Australia in the Commonwealth Games and Olympic Games marathons.
References

• Clark, A., Mach, N., & Platel, A. (2024). Sports-related gastrointestinal disorders: From the microbiota to the athlete. Microorganisms, 12(4), 804.
• Hughes RL, Holscher HD. (2021). Fueling Gut Microbes: A Review of the Interaction between Diet, Exercise, and the Gut Microbiota in Athletes. Advanced Nutrition,12(6):2190-2215.
• Staudacher, H. M., & Irving, P. M. (2024). The forgotten carbohydrate in sports nutrition recommendations. Sports Medicine.
• Gaskell, S. K., & Costa, R. J. S. (2024). Use of carbohydrate, gluten-free, and FODMAP-free diets in preventing gastrointestinal symptoms in endurance athletes: A systematic review. Journal of the International Society of Sports Nutrition, 21(1), 45.
• Barbagallo, M., & Dominguez, L. J. (2010). Magnesium and aging. Current Pharmaceutical Design, 16(7), 832–839.