A basic overview of understanding scientific research regarding nutrition studies.

Here is a quick guide to understanding some research studies. When it comes to finding out what has been proven (or not dis-proven) in regards to healthy living, it may seem like there are conflicting studies out there. Do a Google search and you probably can find a ‘study’ that confirms whatever bias you have.

Critical thinking is a great tool to have when it comes to deciphering what research has really shown when it comes to nutrition.

Here is a quick guide to help understand what the studies actually are and how it relates to how we live.

In Vitro

                A test done ‘within the glass’, like a petri dish. This method has its benefits to control the environment and variables being studied. This is great to determine what is happening on a cellular level but does not translate so well in what will happen within the human body or in real life.

Animal Research

                Typically done to test the safety of a study before completing on humans. Environment and variables are easily controlled, and some animals have similar biology to humans. These studies are not best used to predict human behavior, nor the results be directly related to humans.

Editorials

                Ideas and opinions of experts in their respective area. Good for keeping an open and unbiased mind.

Randomized Control Trials

                Help evaluate casual relationships while controlling confounding (complex) variables, gives a general standard. Usually costs a lot to perform and does still have outliers.

Observational Studies

                There is a lack of control over variables, doesn’t provide a good snapshot, and the ‘observer’ must be very good at recording and interpreting results. Does help find correlations between findings (NOT causation) and can provide a good picture of effects of groups of people (think stereotypes).

• Prospective Cohort: find, interview, follow (trustworthy, confounding variables not controlled)
• Retrospective Case-control: find, split into groups, and interview (most feasible, subject recall is usually bias)
• Cross-sectional: find, split, find habits/exposures (quick snapshot, hard to interpret)

Systematic Review

                Collects and summarizes all empirical evidence to answer a defined research question. Can include a meta-analysis.

Meta-analysis

                Uses statistical methods to summarize the results of studies and tries to produce an estimate of treatment effect.

See Nutrition Myths for a better understanding of how research can be misinterpreted.