To make an informed nutritional opinion, you need to use your background in nutrition science, applied nutrition, statistics, and research design.

If you want to learn more about what a particular herb is useful for, don’t just look it up in an herb encyclopedia.

GO TO THE SOURCE.
(Have you heard that before?)
The public is counting on you, the nutrition professional to make a sound, informed opinion based on your expertise, not the opinion of some Joe "I think I’ll write a book and make some money" Blow.

To evaluate information, do a literature search to find out what articles have been published in peer-reviewed journals.

Then find those articles and read them carefully yourself, evaluating according to guidelines found elsewhere in this tutorial.

Read the review articles, epidemiological studies, animal and human studies, and clinical trials.

Find out if similar studies have been done yielding similar results. Look at the number of subjects in the studies and if they are representative of specific age, gender, or ethnic groups.

If insufficient information exists to draw a specific conclusion or to make dietary recommendations, DON’T BE AFRAID TO SAY SO.