The Truth Behind Common Nutrition Myths

For decades, low-fat dietary guidelines led many people to believe that consuming fat was the main driver of weight gain. Research has since clarified this picture considerably. The body stores excess energy — from fat, carbohydrates, or protein alike — as body fat when calorie intake consistently exceeds expenditure. Fat itself, at 9 calories per gram, is calorie-dense, so portion size matters, but the source of those calories matters too. Unsaturated fats found in foods like olive oil, avocados, and nuts are associated with cardiovascular benefits in multiple large studies. Trans fats and excessive saturated fats carry different risk profiles. Replacing fat with refined sugar — as many low-fat processed products did — has not proved to be a health improvement.

Carbohydrates encompass a wide range of foods: refined white bread and added sugars sit at one end; legumes, whole grains, fruits, and vegetables sit at the other. These groups behave very differently in the body. Whole-food carbohydrates provide fibre, vitamins, and sustained energy. Rapidly digested refined carbohydrates can drive blood sugar spikes and may contribute to overconsumption. The distinction matters enormously. Populations with high carbohydrate intakes — particularly from whole plant foods — consistently show favourable metabolic health outcomes in observational research. Blanket avoidance of carbohydrates ignores this nuance. See also our article on dietary fibre: the nutrient most people underestimate for a deeper look at one of carbohydrates' most valuable components.

The appeal of skipping meals is intuitive: fewer eating occasions should mean fewer calories. In practice, research on hunger hormones like ghrelin shows that skipping meals tends to amplify appetite and reduce dietary control at subsequent meals. This can lead to larger portions and a preference for higher-calorie foods. Structured approaches to meal timing — including some forms of intermittent fasting — have been studied with mixed results, and their appropriateness varies significantly by individual. For most people, regular balanced meals that include protein and fibre do more to support satiety and consistent energy than meal elimination strategies.

This myth likely stems from the fact that people with chronic kidney disease (CKD) are often advised to limit protein intake, because impaired kidneys struggle to process protein waste products. That clinical context has been incorrectly generalised to healthy individuals. Multiple systematic reviews have found no evidence that higher protein intakes within reasonable ranges harm kidney function in people without underlying renal conditions. That said, extremely high protein intake — far beyond typical dietary recommendations — has not been studied comprehensively over very long timeframes. Anyone with a kidney condition, or a family history of one, should discuss protein intake with their physician before making significant dietary changes.

Organic agriculture prohibits synthetic pesticides and certain fertilisers, which is the primary reason many consumers choose it. Whether that translates into meaningfully higher nutrient levels has been examined in numerous comparative studies, and the findings are generally inconsistent. Some analyses find slightly elevated levels of certain antioxidants in organic crops, likely due to plants producing more defensive compounds when not protected by pesticides — but the differences are small and their clinical relevance is unclear. Eating more fruits and vegetables of any kind — organic or conventional — consistently shows positive associations with health outcomes in population research. Pesticide residue concerns are separate from nutritional value and depend on the food, farming practice, and washing method.

The term 'superfood' is a marketing label, not a scientific classification. While foods like blueberries, kale, and salmon do contain notable concentrations of beneficial nutrients, their effects are studied in the context of overall dietary patterns — not as isolated correctives. Nutritional research consistently shows that it is the cumulative pattern of eating over time, not the presence of any single ingredient, that drives long-term health outcomes. Diets associated with reduced chronic disease risk — such as the Mediterranean and DASH patterns — are characterised by variety, plant food abundance, and limited ultra-processed foods. For an evidence-grounded look at these patterns, see our article on eating patterns that science supports.