From curd to kimchi: How fermented foods support a healthier you

National nutrition week: Fermented foods enhance gut bacteria, aid digestion, and strengthen immunity, offering everyday benefits rooted in culture and backed by science

Fermented foods have been part of our diets for centuries. From curd and pickles in India to kimchi in Korea and sauerkraut in Europe, they are a staple of diets across the world. Recently, fermented foods gained global attention for their link to gut health, immunity, and overall well-being. They bring together nutrition and tradition, making them valuable for modern health. But experts suggest that they should be enjoyed in moderation.

 

What makes fermented foods good for us? 

Fermentation is a natural process where microorganisms like bacteria or yeast break down complex food components. This process not only preserves the food but also enhances its nutritional profile.

 

 

When food undergoes fermentation, it often produces short-chain fatty acids, which support digestion and nourish the cells lining our gut. “Interestingly, a similar process occurs in our gut, where food is broken down into smaller components that are easier to digest. Fermentation also enriches food quality by improving nutrient availability and enhancing flavour - making foods tastier while adding a nutritional edge,” says Dr Saswata Chatterjee, gastroenterologist at The Calcutta Medical Research Institute (CMRI).

 

Fermentation boosts the nutrient profile of foods by increasing B-vitamins (especially B12 in some ferments), vitamin K2 (notably in aged ferments), bioactive peptides, and organic acids like lactic and acetic acid, shares Dr Sukhvinder Singh Saggu, director - minimal access, GI & Bariatric Surgery at the CK Birla Hospital, New Delhi. “It also generates enzymes that help break down carbohydrates, proteins, and fats, and it reduces anti-nutrients such as phytates and oxalates, improving mineral bioavailability for iron, zinc, calcium, and magnesium. Many ferments carry live microbes [probiotics] such as Lactobacillus and Bifidobacterium, and even when not consumed ‘live’, their cell components and metabolites [postbiotics] can confer benefits,” explains Dr Saggu.

 

Gut health and the microbiome

 

You’ve probably heard the phrase – ‘a healthy gut means a healthy you’. Fermented foods introduce probiotics (good bacteria) that restore balance, fight harmful microbes, and improve digestion. Live-culture ferments introduce beneficial microbes and, just as importantly, their metabolites (short-chain fatty acids, bacteriocins, and organic acids) that help crowd out pathogens, lower gut pH, and nurture commensal species, says Dr Saggu. “Regular intake tends to increase microbial diversity and resilience, two hallmarks of a healthy [gut] microbiome,” he says.

 

He further explained that fermentation pre-digests complex carbs and proteins, making foods gentler on the stomach and easier to absorb. Enzymes produced during fermentation assist lactase-deficient individuals with dairy ferments like dahi/ yogurt. The reduction of antinutrients, such as phytic acid in cereals and legumes, enhances the absorption of iron and zinc, which is relevant for vegetarian diets. Dr Saggu also mentions that organic acids slow gastric emptying slightly and improve mineral solubility, while bioactive peptides can support gut motility and reduce post-meal bloating in some people.

 

Impact on immunity and blood sugar

 

A strong immune system begins in the gut. By supporting gut bacteria, fermented foods may indirectly boost our immunity, helping the body defend itself against infections. Speaking to Business Standard, Dr Saggu says, roughly 70 per cent of immune activity sits in and around the gut. Fermented foods can modulate immune function by enhancing gut-barrier integrity, and promote regulatory T-cell responses that keep inflammation in check.

 

He further explains, “Fermented foods may improve insulin sensitivity via SCFAs (especially acetate and butyrate) that signal through gut-hormone pathways (GLP-1, PYY). Organic acids can moderate the meal’s glycemic impact by slowing carbohydrate digestion and gastric emptying. Fermenting grains/ legumes reduces glycemic index and enhances resistant starch formation after cooling. Weight-management benefits also arise indirectly through increased satiety and reduced systemic inflammation.”

 

Fermented foods and different health conditions

Conditions where fermented foods are beneficial:

• Antibiotic-associated diarrhea and mild IBS symptoms: yogurt, kefir, and curd rice often help restore balance
• Lactose intolerance: cultured dairy is typically better tolerated/processed by body
• Iron/zinc deficiency risk: fermented cereals/legumes (idli/ dosa batter, dhokla, kanji) can improve mineral uptake
• Periodontal/ oral health: fermented dairy may reduce harmful oral bacteria
• Vaginal health: some evidence supports Lactobacillus-rich diets for better vaginal health.

 

Conditions where fermented foods can be avoided/used with caution:

 

• Immunocompromised, very elderly, or critically ill: avoid unpasteurised, poorly handled homemade ferments
• Histamine intolerance or migraines: aged/fermented foods (kimchi, sauerkraut, vinegar pickles, cheese) can trigger symptoms
• Active Small Intestinal Bacterial Overgrowth (SIBO): ferments may worsen bloating
• Hypertension: salt-heavy pickles/achaar can raise sodium load
• People on MAO-inhibitor medications (monoamine oxidase inhibitor): tyramine-rich ferments (aged cheese, some pickles) can have adverse effects
• Pregnancy: prefer reputable, hygienic sources and avoid questionable unpasteurised products.

 

While fermented foods are generally safe, eating too much can cause bloating, gas, or even trigger discomfort in sensitive individuals.

“Moderation is essential. Eating too much fermented food can sometimes lead to bloating or digestive discomfort. In individuals with weakened immune systems, overconsumption may increase the risk of infection, since fermented foods contain live bacteria and yeasts,” advices Dr Chatterjee.  "Packaged versions with added salt or preservatives can also cause water retention and blood pressure concerns," highlighted Dr Partap Chauhan, founder of Jiva Ayurveda.

 

India’s traditional fermented foods: Local superfoods 

India has a rich tradition of fermentation. As National Nutrition Week shines a spotlight on healthier food choices, traditional Indian fermented recipes deserve attention for their role in affordable nutrition and long-lasting health benefits.

 

• Dahi/chaas → Source of lactic acid bacteria, supports gut health.
• Idli/dosa/dhokla batter → Reduces phytates, improves protein digestibility.
• Rice-based ferments (kanji, pakhala) → Provide organic acids; cooling increases resistant starch.
• Fermented bamboo shoots and leafy ferments → Rich in fibre, unique probiotics.
• Pickled vegetables → Support microbial diversity if prepared hygienically.

"Fermented foods sit at the intersection of tradition and science. They nourish your gut, boost immunity, and enhance nutrient absorption, provided you choose wisely and respect your body’s signals. If you can strike that balance, fermented foods can become more than just condiments on your plate – they can be daily allies for long-term health," said Dr Chauhan    

  From kitchens to public health programmes 

Experts suggest some ways to integrate traditional ferments into public health programs in India:

 

• Mid-day meals & ICDS (Integrated Child Development Services): Incorporate safe, low-salt dahi/chaas or seasonal fermented millet/cereal batters to improve protein and micronutrient absorption.
• Anaemia & maternal health: Promote fermented cereal-pulse batters and probiotic dairy in antenatal programs to enhance iron/zinc uptake alongside iron–folate therapy.
• Community kitchens & self-help groups: Train women’s self-help groups in hygienic fermentation, standardised starter cultures, and low-sodium recipes; link to FSSAI hygiene modules.
• Fortification with fermentation: Combine biofortification/ fortified staples with fermentation to maximise absorption; distribute shelf-stable starters through primary health centres and Anganwadis.
• Urban slums and workplaces: Low-cost chaas/ dahi carts, fermented millet snacks, and probiotic kiosks in industrial canteens with ensured cold-chain and quality checks.
• Behaviour change communication: Localised educational materials featuring culturally familiar ferments (idli/dosa, kanji, chaas) with simple prep steps, portion guidance, and safety tips.
• Monitoring and safety: SOPs for salt limits, clean water use, fermentation times/temperatures, and periodic microbiological testing via district labs.

   

Agenda of National Nutrition Week 

National Nutrition Week in India is observed in the first week of September. It is led by the Ministry of Women and Child Development through its Food and Nutrition Board and supported by the Ministry of Health and Family Welfare. The campaign promotes awareness about healthy diets and good eating habits across communities.

 

In 2025, the theme is ‘Eat Right for a Better Life’, focusing on balanced nutrition, healthy food choices, and educating families and students to improve well-being and prevent malnutrition. 

 

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This report is for informational purposes only and is not a substitute for professional medical advice.