Activity: Evaluate a Scientific Article

Next up, we'll review some examples that are more straightforward than the social media post.

Let's imagine that after you've reviewed the social media post, you do a search for scientific evidence around MSG (or monosodium glutamate) and brain function. You search a database and find an article about MSG:

Fernstrom, John D. “Monosodium Glutamate in the Diet Does Not Raise Brain Glutamate Concentrations or Disrupt Brain Functions. Annals of nutrition & metabolism vol. 73 Suppl 5 (2018): 43-52. doi:10.1159/000494782

Review the article's information here, Links to an external site. but don't worry about reading the entire article right now. 

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Take a moment to skim the article's abstract:

The non-essential amino acid glutamate participates in numerous metabolic pathways in the body. It also performs important physiologic functions, which include a sensory role as one of the basic tastes (as monosodium glutamate [MSG]), and a role in neuronal function as the dominant excitatory neurotransmitter in the central nervous system. Its pleasant taste (as MSG) has led to its inclusion as a flavoring agent in foods for centuries. Glutamate's neurotransmitter role was discovered only in the last 60 years. Its inclusion in foods has necessitated its safety evaluation, which has raised concerns about its transfer into the blood ultimately increasing brain glutamate levels, thereby causing functional disruptions because it is a neurotransmitter. This concern, originally raised almost 50 years ago, has led to an extensive series of scientific studies to examine this issue, conducted primarily in rodents, non-human primates, and humans. The key findings have been that (a) the ingestion of MSG in the diet does not produce appreciable increases in glutamate concentrations in blood, except when given experimentally in amounts vastly in excess of normal intake levels; and (b) the blood-brain barrier effectively restricts the passage of glutamate from the blood into the brain, such that brain glutamate levels only rise when blood glutamate concentrations are raised experimentally via non-physiologic means. These and related discoveries explain why the ingestion of MSG in the diet does not lead to an increase in brain glutamate concentrations, and thus does not produce functional disruptions in brain. This article briefly summarizes key experimental findings that evaluate whether MSG in the diet poses a threat to brain function.

Looking Deeper

Let's take a closer look at this source's details shared in the  including author(s), publisher, and the type of source.

  • Author(s): John D. Fernstrom, Department of Psychiatry, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine
  • Type of Source: Peer Reviewed Scientific Journal
  • Journal Name: Annals of Nutrition and Metabolism

After this short investigation, we can review our guiding questions to determine if this source is trustworthy. Click next to continue.