Category: Evidence based nutrition

Millions of health articles are published annually, with randomized controlled trials (RCTs) sitting atop the evidence hierarchy for assessing interventions. The reason randomized controlled trials are considered the gold standard of nutrition research is their unique ability to reduce bias and provide the strongest evidence for cause-and-effect relationships between dietary interventions and health outcomes.

While preliminary laboratory and animal studies have suggested that grape seed extract may inhibit aromatase, the enzyme that produces estrogen, human clinical trials have largely failed to produce significant results. This has led to widespread confusion and often conflicting advice regarding its true impact on hormone levels.

Despite its popularity, a 2013 systematic review published in the *American Journal of Clinical Nutrition* found no scientific evidence to support the health benefits of the blood type diet. This research directly challenges the central claims, including the idea behind 'Why should B+ blood type avoid wheat?'