Protein, fibre, and blood sugar: the basics for midlife energy
Adequate protein and fibre intake is associated with more stable energy across the day. This guide covers practical amounts and sources.
Two nutrients receive less attention than they deserve in conversations about midlife energy: protein and fibre. Neither is glamorous. Both are consistently associated with more stable blood sugar, better satiety, and sustained energy across the day.
Why protein matters more in midlife
Muscle mass naturally declines with age — a process called sarcopenia — and the rate of decline increases after menopause. Adequate protein intake, combined with resistance exercise, is the most effective way to slow this process.
Beyond muscle, protein is associated with reduced hunger between meals and more stable blood sugar compared to a high-carbohydrate meal of similar calories. This matters for energy because large swings in blood sugar are associated with fatigue, irritability, and cravings.
A practical target: Most research on midlife women suggests that 1.2–1.6g of protein per kilogram of body weight per day is associated with better outcomes for muscle maintenance and satiety than the commonly cited lower figures. For a 70kg woman, that is roughly 85–110g per day.
Sources: Eggs, fish, chicken, Greek yoghurt, cottage cheese, legumes, tofu, and tempeh. Spreading protein intake across meals rather than concentrating it in one sitting is associated with better muscle protein synthesis.
Why fibre matters
Fibre slows the digestion of carbohydrates, which flattens the blood sugar curve that follows a meal. It also supports gut microbiome diversity, which is increasingly associated with immune function, mood regulation, and metabolic health — though the research here is still developing.
A practical target: The NHS recommends 30g of fibre per day; most adults consume around 18g. Increasing fibre gradually (to avoid digestive discomfort) and alongside adequate water intake tends to be well tolerated.
Sources: Vegetables, fruit, legumes, oats, wholegrains, nuts, and seeds. Variety matters as much as quantity.
What this does not mean
This is not an argument for low-carbohydrate eating. Carbohydrates are not inherently harmful. The relevant question is their quality and context — a meal that includes protein, fibre, and complex carbohydrates will produce a different blood sugar response than the same calorie count from refined carbohydrates alone.
If you have specific concerns about blood sugar, speak to a clinician before making significant dietary changes.