Health science, especially as it relates to nutrition, can often be unclear. For instance, health.gov 2015-2020 guidelines recommend low-fat and fat-free diary options. Miles Hassell, MD (an internist at Providence St. Vincent Medical Center in Portland) recommends whole or 2% options instead of lower fat options. In the face of such contradiction from two seemingly reputable sources, it is easy to doubt most nutrition science. Although I am using nutrition science as an example here, it is important to note this can be said of most any branch of science.
By understanding the way in which scientific research works, we can see that there are times to doubt the latest research, but there are also times to invest trust in long-standing findings. Science is a tree that grows with every finding. New findings either support or contradict old findings. In this way, either a hypothesis (e.g. low-fat yogurt is healthy) is strengthened and becomes a more firm branch, or is found to be false and pruned. An example of a very strong branch in nutrition would be high sugar diets being detrimental to health.
Tree created by: <a href=”http://www.freepik.com/free-photos-vectors/tree”>Tree vector designed by Freepik</a>
So how do you decide if an idea is a strong or fledgling branch? Generally, stronger branches will have the following:
- Agreement within the scientific community*
- Been around for awhile
- Many appearances in peer-reviewed journals
*Note: agreement is not always 100%. With over 7 billion people in the world, there will always be those that contradict. However, general scientific community consensus means that you will not have large peer-reviewed journals (Nature, Science, New England Journal of Medicine…) disagreeing with each other.
Science is not always right. Towards the outer reaches of our knowledge, there is a glorious mess of experiments, conclusions, and confusion. Overtime and with more experiments, we prune the tree and limbs become stronger until where was a mess is now a coherent supporting structure. The ideas that increasing exercise, eating at least 5 vegetable servings a day, and reducing soda consumption increases health are long standing beliefs we can invest in.