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Dieting, Nutrition and the Scientific Method

  1. Jun 29, 2012 #1
    The Better Half is always researching the latest diet trends, theories, observations, etc... I check out the articles every now and then and it seems like the overlaying problem with all these studies is the removal of variables in a study.

    Is it possible to accurately measure/test nutrition and dieting on humans? If not, does that make nutrition a pseudo-science?
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  3. Jun 29, 2012 #2

    jim mcnamara

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    Your question is not clear - are these articles you mention in peer reviewed journals, or something meant for non-scientists like maybe USA Today?

    Could you please provide a littile more detail about one of those articles?

    Nutrition is a Science.

    Some aspects of what are ostensibly labelled as Nutrition articles are "interesting". There were a few studies done in the past that had funding from entities with a clear motive. For example, one of the problems is that there is potential financial impact to agribusiness from research, so there have been studies and also reviews of other research data done by organizations like the Sugar Institute (www.sugar.org). Many articles they have funded researc on are simply chemistry and Food Science - preparation, handling, processing. Others are more interesting.

    This is a simple example of trying to deflect causes of obesity away from sugar based ingredients using somebody else's data. And I'm not implying anything about what causes obesity.

    http://www.sugar.org/sugar-and-your-diet/caloric-intake.html [Broken]

    This is not science per se, is this what you mean? It is more like a political ad, IMO.
    Last edited by a moderator: May 6, 2017
  4. Jun 29, 2012 #3


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    I think the paleolithic diet wiki demonstrates a good approach to the problem:


    It contains a lot of peer-reviewed references for your interest (genetic arguments to observational studies to intervention studies) that might demonstrate how scientific methods are helpful in determining nutritional value.
  5. Jun 30, 2012 #4


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    In addition to what has already been offered please note that when considering a source anyone identifying as a "nutritionist" isn't a member of a credible medical profession. A medically trained specialist in diet and nutrition is called a "dietician".
  6. Jun 30, 2012 #5
    Thanks everyone! I understand we can accurately test the bio-chemical processes of food and the reactions that take place in the body.

    What seems to be less clear are the long term effects of certain diets. Since humans are extremely varied and we have a vast "ability" to survive on a wide range of foods...it would seem that "proving" a certain diet is more beneficial than another is difficult. In other words we can only limit one factor in overall health studies of dieting. Many psychologists would argue that overall health is strongly rooted in mental health. So since we cannot isolate and control variables in health/nutrition studies (I consider nutrition to be different from bio-chemistry) it seems that the science around nutrition really isnt science but more like guided advice or correlation.

  7. Jun 30, 2012 #6


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    I suggest you read up on cohort studies and how they are used.
    Whilst psychological state of the patient is an important factor in overall health to say it is "strongly rooted" is taking it to far. Also nutrition is a great thing to study in this regard especially with the links between stress, happiness and food.
    Yes, considering your admitted ignorance on this subject (you say you've checked out an article every now and then but it's not even clear if these are peer reviewed) what makes you think your opinion on this matter is valid? If you are unclear on how nutrition studies are done how can you possibly suggest that it isn't a science? Furthermore you can consider nutrition to be different from biochemistry all you like but it largely is not, understanding the molecular processes underlying nutrition both in terms of digestion and the roles of individual nutrients is all intimately linked to the field and very much science.
  8. Jun 30, 2012 #7


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    Do you have some examples of research that you're talking about? The field is really big. Animal models can be used to study the impact of food, there the variables can be tightly controlled. Then there are the population association studies that I would take with a big scoop of salt.
  9. Jun 30, 2012 #8
    This is simply a topic for discussion. Yes I know that there is firm scientific method being utilized in a lot of portions of dieting and nutrition. What I was asking (and perhaps I should have clarified)is if the scientific method can really be used in long term effects of overall health? Can the mental component of overall health be measured (highly unlikely)? If not then how can we use the scientific method when we talk about health, dieting and nutrition?

    I never said my opinion was valid...simply wondering if we can use accurate and predictable methods when we are discussing overall health.
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