Red flags for a supplement's clinical trial include incredibly fast publication, journals with no impact factor, and the company running the study themselves without ethics approval.

In a 2014 study, beetroot juice supplementation reduced blood pressure by an amount comparable to the impact of prescription blood pressure medications.

Saliva tests measure nitrite, and investigations show no correlation between higher saliva nitrite and the elevated blood nitrite needed to create nitric oxide.

Research shows L-citrulline is more effective than L-arginine itself at raising blood levels of L-arginine, although its performance benefits are still underwhelming.

A single bowl of spinach soup used in a study contained 845mg of nitrate, whereas a supplement like Nitralis contains only 60mg.

An analysis of 24 beetroot products found only five with adequate nitrate levels, including Lakewood Organic, Nudeson, and several 'Beat It' brand juices.

The Nitralis supplement contains at most 60mg of nitrate, which is only about 15% of the ~400mg doses used in clinical trials that showed benefits.

A capsule cannot carry enough nitrate to make a clinically meaningful difference, which is why effective products are typically drinks or juices.