Evidence-based nutrition, in plain English — every entry sourced from clinical research.
Every entry in this collection — sourced, checked and written to be read.
Home blood pressure fell over eight weeks in all four groups, including the control group, and the low-sodium salts lowered urinary sodium-to-potassium ratios. Differences between the groups were not statistically significant, and the authors describe the results as preliminary.
The sodium-to-potassium ratio predicted blood pressure and incident hypertension better than sodium or potassium alone, though its value in normotensive people and in children remains unclear.
In 16 cohort studies, higher potassium intake was associated with a 13% lower risk of stroke, with the lowest risk at about 3,500 mg (90 mmol) a day. This is an observational association.
Across 32 trials, extra potassium lowered blood pressure most in people with hypertension and in those eating more salt, but the relationship was U-shaped: the benefit faded above about 30 mmol (1.2 g) a day extra, and at much higher doses blood pressure rose again in people taking blood-pressure medication. Estimates for high intakes rest on few trials.
Over five years, omega-3 supplementation reduced new autoimmune disease by 15%, a reduction that did not reach statistical significance, while vitamin D reduced it by 22%.
Pooled trials showed omega-3 supplementation significantly reduced fasting blood glucose and insulin resistance, but did not significantly change HbA1c, and variation between studies was high.
Evidence remains too uncertain to say whether omega-3 treats depression in adults: any benefit over placebo was small, imprecise and not clinically meaningful, on low to very low certainty evidence.
Across 86 trials, more long-chain omega-3, mostly from supplements, had little or no effect on death or cardiovascular events overall (high-certainty evidence), but may slightly reduce coronary heart disease deaths and events, and lowers triglycerides. More plant ALA may slightly reduce cardiovascular events and probably reduces arrhythmia.
In this UK cohort, children of mothers with inadequate early-pregnancy iodine status were more likely to have lower verbal IQ and reading scores at ages 8-9.
Across eight small trials (191 people), taking capsaicinoids before a meal cut intake at that meal by about 74 kcal, with at least 2 mg needed; results varied widely between studies, and long-term effects on weight are untested.
Pooling nine trials, chlorogenic-acid-rich green coffee extract was associated with small reductions in systolic and diastolic blood pressure, more pronounced in people with hypertension.
Across 20 randomised trials, green tea catechins were associated with modest reductions in total and LDL cholesterol, with no significant effect on HDL or triglycerides.