When Marie Curie advanced fundamental research, she showed the world that clear methods can dispel myths. We need exactly this spirit in nutrition: fewer myths, more evidence. Instead of relying on headlines, today we follow the data – focusing on decisions that truly improve energy, focus, and longevity.

Myths persist because they are simple. Science is often more nuanced – and helpful. It is crucial to understand how individual dietary patterns affect our metabolism, the insulin responseincrease in insulin following carbohydrates/glucose, the lipid profileslevels of blood fats such as LDL, HDL, triglycerides, and the gut microbiotatotality of microorganisms in the gut. "Natural" isn't automatically better, and "processed" isn't automatically bad. Energy for high performance arises when we smooth out blood sugar spikes, reduce inflammation, and strengthen the gut barrier. This can be achieved through three levers: smart sweetness, protein-smart choices, and fermented diversity.

Stable blood sugar prevents performance dips and cravings – a central myth is that "all sweeteners are bad." Data on stevia show that replacing added sugar leads to fewer calories and can be associated with reductions in weight and waist circumference, without drawbacks for long-term blood sugar levels after a short application duration ^{[1] [2]}. When it comes to protein, source matters. When red meat is more frequently replaced with high-quality plant proteins, LDL and total cholesterol decrease – risk factors for cardiovascular diseases and, consequently, for performance in aging ^[3]. Another lever is fermented foods: they increase beneficial bacteria and their short-chain fatty acidsmetabolic products like butyrate that reduce inflammation, which can strengthen the gut barrier and lower systemic inflammation – both relevant for energy, recovery, and immune protection ^{[4] [5]}. Finally, fatty fish such as salmon or mackerel provide omega-3 fatty acids that support the heart, brain, and inflammation regulation – with measurable effects on metabolic and inflammatory processes ^[6].

Regarding sweetness: a pilot intervention where participants replaced added sugar with stevia table sweetener over 90 days showed significant reductions in body weight and waist circumference without reported side effects – practically relevant because it mirrors simple swaps in everyday life ^[1]. Additionally, a systematic review with meta-analysis suggests that stevia can moderately lower blood glucose in the first weeks to months without showing a consistent effect on insulin or HbA1c; the authors call for larger, longer-duration randomized trials – an indication that the benefit is short-term and dose-dependent ^[2]. For protein, a network meta-analysis of randomized studies shows: replacing red meat with plant protein sources lowers LDL and total cholesterol more than with red meat – a direct surrogate benefit for cardiovascular risk in terms of prevention ^[3]. For fermented foods, a recent review consolidates the evidence that yogurt, kefir, and similar products diversify the microbiota, promote tight-junction proteins of the intestinal wall, and favorably affect metabolic markers such as blood fats and blood pressure; a controlled RCT in healthy young adults additionally showed that kefir specifically increases lactate-producing and SCFA-associated bacteria – a plausible mechanism for improved gut function and inflammation modulation ^{[4] [5]}. Finally, a review on fish consumption underscores the role of fatty fish as a source of omega-3, vitamin D, and iodine, associated with cardio- and neuroprotective effects; for precautionary reasons, certain mercury-rich species should be avoided by pregnant women and children – evidence meets nuanced risk management here ^[6].

- Consistently replace added sugar in coffee, tea, muesli, and baking recipes with stevia or monk fruit. Start with a 2–4 week "sweet swap," observe energy levels and cravings, and adjust the quantity to taste. The data supports better short-term glucose control and fewer caloric burdens ^{[1] [2]}.
- Plan for 2–3 fish meals per week, with at least two of them being fatty fish (e.g., salmon, mackerel, herring). Use frozen or canned variants (in water/olive oil) to lower barriers. Pay attention to mercury-poor species during pregnancy/breastfeeding and for children; avoid swordfish, shark, bluefin tuna, and pike ^[6].
- More frequently replace red meat with plant proteins: lentil Bolognese instead of ground meat, tofu/tempeh stir-fry, bean chili. Goal: choose plant-based sources as the main protein on 4–5 days per week. This improves LDL and total cholesterol – a plus for heart health and longevity ^[3].
- Incorporate fermented foods into your daily diet in small portions: 150–200 g of natural yogurt or kefir, 2–3 tablespoons of sauerkraut or kimchi with lunch/dinner. Start slowly and increase depending on tolerance. This promotes beneficial bacteria, gut barrier, and inflammation balance ^{[4] [5]}.

The coming years will bring more precise nutrition: personalized ferments, targeted omega-3 strategies, and smart sugar replacements tailored to microbiome and metabolic profiles. With better studies and digital feedback loops, nutrition will evolve from an intuitive understanding to a measurable performance strategy.