Critical Thinking and Nutritional Bias

Tuesday, July 17, 2012

When I started writing my post on cognitive bias and perception, I began thinking really hard about self interest, motivational psychology, and self accepted truths we have come to believe. How do we arrive at these conclusions? Well for the most part we have been influenced by a well crafted augment from a nutritional source to adopt a set of beliefs based on what we perceive as a logical conclusion. The focus of this blog post is to examine the art of arguments in nutrition. How to sniff out the bad arguments, how to critically examine an argument rather then just viewing then entire argument as accepted or invalid, and how to apply critical thinking skills to your health goals.

This seems to be an all too common theme amongst Nutrition Gurus, Registered Dietitians, Health food Blogers, Independent health researchers. A lot of contradictions and it makes us think. They can't all be right at the same time, Thus when we are made aware of these contradictions our natural response is to recoil to reject or modify one or more of them so as to bring back stability and consistency to our thought process. We need some logical philosophy to accept other wise our minds would just be in chaos 24/7. Which Brings us to Critical Thinking in Nutrition and health

A lot of the ideas and structures were mimicked from http://www.criticalthinkeracad I do not claim the rights to any of these ideas. I'm simply reiterating important knowledge.

"Philosophy means the love of wisdom, to have wisdom is to have knowledge of the true and the good, to act wisely is to act on the basis of that knowledge. "

The Goal of Critical thinking:

Our goal is not to win an argument but to understand an issue from all sides with clarity; to understand the strengths and weaknesses of different positions on the issue and eventually get to the truth of the matter. That is seeking truth and understanding and not just winning.

"Critical thinking is the intellectually disciplined process of actively and skillfully conceptualizing, applying, analyzing, synthesizing, and/or evaluating information gathered from, or generated by, observation, experience, reflection, reasoning, or communication, as a guide to belief and action. In its exemplary form, it is based on universal intellectual values that transcend subject matter divisions: clarity, accuracy, precision, consistency, relevance, sound evidence, good reasons, depth, breadth, and fairness." -(2)

"Learning critical thinking skills will help immunize us(not all of us) from powerful influences by learning to discriminate between good and bad reasons for belief and action."

Why do we use critical thinking?

1. Self Defense
2. Personal Empowerment
3. Civic Duty
4. Truth and Wisdom

The 5 essential components for critical thinking: All five areas are mutually dependent on each other

1. Logic
2. Argumentation
3. Rhetoric
4. Background Knowledge
5. Attitudes and Values

Arguments are not just logical they are psychological. The psychology of belief and persuasion can be powerful tools in an argument. Actually it's interesting to note that the argument and rhetoric components can be confused with each other. There is a difference between having a good argument and using persuasive rhetoric. Some people can use bad arguments but be very persuasive with there manipulative rhetoric. However persuasive rhetoric can be good and bad. Knowing your audience, how to persuade your audience and knowing the context of the audience's thought process is important in critical thinking. Although as stated above, it is just one part of the equation.

Different types of background knowledge:

1. Disciplinary (subject matter) Knowledge

2. Intellectual history of a debate/issue

3. Knowledge related to the psychology of belief and judgment

Just remember that no amount of logic or argument can make up for lack of background knowledge. Trying to get away with lack of background knowledge is referred to as the act of Bull sh$%ting

What to avoid when using critical thinking: Looking only for weakness in an argument and using misrepresentations

It's easier to look for weaknesses in someones argument then to take the time to intellectually understand their side of the issue and how they arrived at those arguments. When you look at a position through such a selective view you are more likely to misrepresent the idea and think you have understood it when you really haven't. You may also miss the small kernel of wisdom that may exist or be waiting to be acknowledged. Try to avoid Knee jerk reactions and come to better understanding of the other persons position.

Other problems include bringing in irrelevant information to distract from the original issue.

What to do instead: Looking through the mind of another and staying on topic

View the world of that character through their eyes, a person needs to forget who they are temporarily so another persona can be projected through them. You need to be able to articulate their rationale for their position and get them to say something like "yes that's exactly why I hold onto my nutritional beliefs, you get it"

Make sure that you stay on topic as well and try not stray away from the main topic. I feel like we all learned this in Ms. Ito's 5th grade class but decided it was irrelevant at the time.

Fallacies in the form of Conditional Chains and The Ad Hominem

a deceptive, misleading, or false notion, belief, etc.: That the world is flat was at one time a popular fallacy. - (4)

Examining Conditional Chains

A -> B -> C-> D

1) A Chain of conditional Inferences is only as strong as it's weakest link
2) Weakness in the links compounds. The strength of the whole chain is usually much weaker then the weakest individual link

Humans beings are very vulnerable to these types of chain conditioning/slippery slope mentalities. Misjudging the chain of inferences can lead to a misleading conclusion and chains can be more notably seen as a group of probability inferences. People tend to be very bad at estimating compound probabilities and tend to overestimate and then overstate the claim based on these skewed probabilities.

Direct TV uses this type of conditioning chain in their commercials against cable.

Ad Hominem meaning "to the man" is the fallacy of rejecting a argument because we don;t like something about the person. We choose to reject the argument, even if it is a good argument, because we do like the person for no other reason then that the guy just "sucks ass".

This type of fallacy reminds of the Underpants Gnomes episode of South Park in which a new coffee company ( Starbucks) is invading the town. The boys go onto a debate show to present their main arguments against the coffee company. (

MEDIATOR: Okay, Now for the other side of the argument we turn to our young, handsome lads. Boys, your thoughts. Come on, boys, don't be shy. What's your principal argument?

CARTMAN: This guy sucks ass! - Ad Hominem

MEDIATOR: Great argument! You win, boys!

Factors that affect our thought process


1) A rule of thumb or a short cut we use to simplify a cognitive task

2) We're usually not aware of the heuristics we are using

3) Heuristics do not give optimal solutions just good enough ones


1) The predictable effect of using a given heuristic:

2) Often produces a GAP between how we ought to reason and how we in fact reason

For instance: one bias that is commonly used is the Anchoring Effect -

"During normal decision making, anchoring occurs when individuals overly rely on a specific piece of information to govern their thought-process. Once the anchor is set, there is a bias toward adjusting or interpreting other information to reflect the "anchored" information. Through this cognitive bias, the first information learned about a subject (or, more generally, information learned at an early age) can affect future decision making and information analysis." -(1)

Actually if you click on this link
ist_of_cognitive_biases you will find that there are over 100 different types of biases we can use in our thought process without even realizing it to make a decision. We need to be aware of the biases we use to process information that influence own judgment when we are using critical thinking especially if those process make us venerable to errors.

Why we use science in Critical Thinking:

1) Humans beings are prone to biases that lead to error

2) Scientific methodology aims to neutralize the effects of the biases, and thereby reduce human error

We as humans exert a trait known as Undisciplined Pattern Recognition:

"is the task of classifying raw data using a computational algorithm (sometimes appropriate action choice is included in the definition). The term is from machine learning, but has been adapted by cognitive psychologists to describe various theories for how the brain goes from incoming sensory information to action selection." -(3)

Pattern recognition can be an extraordinarily valuable tool for extracting meaning and relevant information from our environment. However there are negative aspects. We can add meaning to patterns that don't have meaning or impose meaningful data on a experiences when there is nothing there.

- We suck at weighing evidence:

1) Biased search for evidence

2) Biased Interpretation of evidence (people set higher standards of evidence for evidence that goes against there hypothesis)

"Science is what we do to keep us from lying to ourselves" - Richard Feynman

Looking for confirming evidence but also dis confirming evidence helps to form a more complete picture instead of a bias search to confirm our own beliefs. Thus, "by accepting and embracing our limitations and fallacies as cognitive agents, rather then denying them or struggling with them, it's possible to improve the quality of our judgements and make more rational decisions than we would otherwise."

"Physicians and other medical practitioners make untold numbers of judgments about patient care on a daily, weekly, and monthly basis. These judgments fall along a number of spectrums, from the mundane to the tragic, from the obvious to the challenging. Under the rubric of evidence-based medicine, these judgments will be informed by the robust conclusions of medical research. In the ideal circumstance, medical research makes the best decision obvious to the trained professional. Even when practice approximates this ideal, it does so unevenly. Judgments in medical practice are always accompanied by uncertainty, and this uncertainty is a fickle companion—constant in its presence but inconstant in its expression. This feature of medical judgments gives rise to the moral responsibility of medical practitioners to be epistemically humble. This requires the recognition and communication of the uncertainty that accompanies their judgment as well as a commitment to avoiding intuitive innovations." -

Your argument should be good and be based on true and plausible premises to arrive at a strong or valid conclusion/inference. Arguments can vary in strength and there are no formal principals of logic that can make this decision for us. Learning the art of arguments is an important aspect of science and since most of health is based on science in this modern era we should thus include argument analyzing into our examining of nutritional inferences so as to improve the quality of our judgments and make more rational decisions.

Keep all of the above in mind when reading nutritional articles, blogs, and websites. Ultimately critical thinking will lead to the truth instead of just arguing over who is right or wrong.

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Member Comments About This Blog Post

    Yup and that is the pattern seeking that people subconsciously do. Looking for articles that fit with their own bias even if the study cited is misrepresented by the interpreter. Too afraid to read something that may in fact "rock" their nutritional world. Critical thinking can be a curse and blessing sometimes.
    2439 days ago
    Impressive analysis.
    2440 days ago
  • no profile photo DANAWALKER4
    2440 days ago
    Some very good points.

    I have found that one of the difficulties in doing the research and trying to come to any sort of decision is that we often don't read about research first-hand. We often hear about an article about the study. Maybe, if we're lucky, we actually read an article from a reasonably reputable source - and are aware enough to pay attention to the words like "think" or "consider it likely". If we do seek out a particular study, we often find that it is summarized by the researchers' opinions and goals and not nearly as definitive as the claims make it sound.
    2440 days ago
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