Every single day, we are bombarded by headlines making claims about what is good for our health and what will inevitably kill us. Most are fallacious, but we would have to do some research of our own to determine this and diving into scientific journals can be quite daunting.
Here are some tips to help with such efforts:
- Realize that journalists are not scientists.
- Headlines in newspapers and on popular internet news sites are written by journalists, not scientists. The person writing the eye catching headline doesn't necessarily know a single thing about the subject matter. His/her single mission is to grab your attention and get you to read their newspaper or website.
- If a claim about a scientific study catches your interest, go directly to the journal that published it. If the news article doesn't cite the study directly, try locating the study's author and/or title within the article. Once you find that, put it into google to find the original paper. By reading the 'Method' and 'Results' of a study yourself, you will be better equipped to draw your own conclusion instead of relying on the interpretations of others.
- When it comes to nutritional science, there are 2 general types of studies that we are concerned with:
- Observational (i.e. cohort or epidemiological) - In these studies, researchers follow large groups of people over long periods of time (long enough for participants to be stricken by disease). Numerous variables (height, weight, age, sex, diet, lifestyle, income, medication, etc.) are recorded along the way and then analyzed at the end of the study. The goal is to find a variable that is related to a given disease (note that I did not say 'causes'). These findings are what future hypotheses are formed from.
- Controlled (i.e experimental or intervention) - Using the hypotheses formed from the results of observational studies, controlled studies are created. Participants of these studies are randomly put into at least 2 groups. The diets of each group will differ from one another while being controlled by the researchers. The results of a properly setup controlled study are the gold standard of the day, but the high costs associated with such studies prevent them from occurring often enough.
- When 2 things are related to one another, it is said that a correlation exists between the two. However, this does not automatically mean that the one causes the other. Therefore, there is no implied causation between the two.
- As an example: If you were to study reading ability and shoe size in this country, you would find that reading ability correlates with larger shoe size. That is, those who read the best tend to have larger shoes than those who don't read as well. I know what you're thinking, this is absolutely preposterous as we all know that having large feet does not cause one to be a better reader. Thus proving that 2 things can be correlated, but not necessarily causative.