What Supplements to Take? Making sense of scientific studies

How to make the smart choice

Every day,  millions of supplement products flood the market claiming to have the answer to all our problems and being backed by scientific clinical findings. Interestingly, both these products seem to look very similar that it would be hard for even experts to sometimes tell the real from the fake. Unfortunately, the U.S. Food and Drug Administration (FDA) can regulate supplements like they do with prescription medications. The REAL question, “How can the ordinary people like you and I avoid ingesting these poisons?

Guide to understanding scientific findings

research studiesI wrote this post to provide you with the necessary information to enable you to spot fake products in the market.

Another reason is to empower you to make an informed choice after reading this post. Lastly, after spending years in medical school and hospitals, I realized that the healthcare system had lost its mind since the insurance company took over control from medical doctors.

Also, health workers’ burnout and the greed to make “Money quick, the root of all evil,” according to the famous saying, has taken root deep down into the soul of many nutritionists and healthcare professionals.

Let’s get started.

Before scientists can confirm that a vitamin or mineral is active, the promising evidence must work its way through a hierarchy of research studies or experiments.

In the case of nutrition and diet, every study has its own unique challenges and restrictions.

Before you blast off to buying the latest supplement trending the media, I suggest that you carefully read and weigh the proof or evidence. Let us briefly look at the vital information you need to know about various studies.

But if you’re already familiar with making sense of scientific findings, you can jump right into “What does Vitamin B12 Do for Your Body?

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What are the various scientific studies?

Laboratory study

These studies are done using animals or samples in test tubes. They can suggest how and why a vitamin, mineral, or phytochemical might work. Yes, humans are higher animals, but the results don’t automatically transfer to the human body.

Observational (epidemiological) studies

These studies were done using a large human population, which can get up to 100,000 or more. These studies can last for years, even up to decades. Scientists gather data at regular intervals.

Basically, people who stay healthy are compared with those who fall sick. Researchers try to find factors that could explain the differences.

These studies can be compelling since they follow these people long-term while they are living naturally. The downside is that still, they can only demonstrate correlation, but not cause and effect. For instance, folks who consume strawberry or blueberries might be healthier because they live healthier lives overall, not because they consume strawberry or blueberries.

Though researchers try to adjust for confounding factors, they still cannot claim real cause and effect.

There are type types of observational studies, although, they both have limitations:

Case-control studies are basically looking at people WITH the diseases(cases) it first identified comparing them with those WITHOUT the disorders (controls). The researchers try to determine which risk factor (s) causing the disease by asking all participants about elements in the past that maybe link with the problem.

The problem with this kind of study is what scientists called “selection bias” (lack of similarities between control and case group).  Another type of bias is when participants have inaccurate recall of things from how they actually occurred).

Cohort studies Researchers start by finding a large population of individuals who don’t have a specific health problem and ask about current risk factors. These folks are later observed for a certain period to see who develops the interested health problem from those who did not.

Although a cohort observational studies design has a more robust pro because participants are routinely questioned about their lifestyle and diet before developing the issue. However, they still frequently depend on self-reports on dietary questionnaires, which can be subjective and less accurate.

Metabolic studies usually comprise a small number of volunteers who consume specially prepared food for a short time. They are intense and strictly controlled. The downside is duration too short of depicting any real outcomes on disease over the long term. The main goal is to look for any changes in risk factors, such as cholesterol, high blood sugar, or blood pressure.

A Randomized controlled trial
(RCTs) is study characterized by random selection and assignment of participants to either a treatment group (those who receive study substance) or a control group (those who take a placebo-which look similar to but are inactive). RCTs are the gold standard.

One of the advantages is that it can show if there is an actual difference, but they may not be long enough to show long-term effects.

Additionally, for the results to be valid, most participants have to stay until the end of the study, which can sometimes be very difficult to achieve. The situation of participants leaving a study can negatively impact the study results or the worst canceling of the study.

Lastly, these studies may use applicants who are in worse or better health compared to the general population like yourself. Thereby making the results not useful to you.

Meta-analysis uses basically uses a statistical tool to analyze past published studies based on similar keywords, looking for similar patterns or outcomes.

One major pro of meta-analysis involves its ability to integrate data from numerous sources of past published studies. A possible downside is that the reliability of the analysis depends solely on the quality of the previous studies.

Another downside has to do with the complication that could arise when different studies used produces non-related findings, making it difficult to interpret.

Okay! Now let us dive into the main reason why you are here.

What to know about the approval seal?

For general information about supplements, you can check the office of dietary supplements.

If you want to determine out if a brand contains all the ingredients they claim to have, go to these three independent organizations’ websites.

NSF International Dietary Supplement Certification

ConsumerLab.com Approved Quality Product Seal

“United States Pharmacopeia (USP) Dietary Supplement Verification Program.”

They offer “seals of approval” that may be displayed on dietary supplement products.

The Seal simply means that a product has successfully “passed the organization’s quality tests for strength, content, and purity (contaminants). These “seals of approval” do not signify that the product is effective or safe to use. Instead, they assure that the product comprises the listed ingredients on the package label and that it does not contain toxic (harmful) contaminants.

How these organizations operate

These are examples of some vitamin and mineral supplements brands that have the “USP approved Seal.”

NatureMade. Available at Amazon.com.

Kirkland Signature. Available at Costco.com but with membership.

Final Thought

It is true that this modern time, it can be difficult to tell the fake from the real product, or if a particular supplement contains the exact ingredients and held up to its claim. My recommendation is that you

begin your detective research by going to your kitchen or bathroom cabinet and check your entire supplement products to make sure they have any of the three seals listed above and the other information. If they don’t, toss them out through the window (figuratively speaking).

Thanks for reading this post. For more information on choosing supplements wisely, click on how to choose your supplement.

I will love to know what you think about this article by leaving a comment or question below.


Harvard Health Publication. available only on Purchased.




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  1. Excellent article, Benson! I am overly cautious about my and my mother’s health, and I completely agree that we must do our research to make sure that various supplements are truly safe and effective to use. My mother takes various supplements to regulate her health and conditions, including melatonin, Benefiber, iron supplements, and Vitamin D supplements. I always carefully read the labels, do my independent research ahead of time, and make an informed decision as to whether these products are legit or junk. I will definitely start visiting the three websites that you mentioned! Great read! God bless you!

    • Hi C.N.,
      I’m so glad you are doing your research prior to buying supplements for you and your mother. We live in a world now that each individual has to do their due diligence because it seems like the organizations (FDA) put in place to protect us are failing.
      Thanks for stopping by.
      God bless you too.


  2. “…the healthcare system had lost its mind since the insurance company took over control from medical doctors…” I couldn’t agree more with you. This is not only the case in the US, but over here in EU too.
    Very informative article on the quality. The EU has similar control programs.
    Thanks for your research!

    • Hi Hannie,
      You’re welcome and thanks for reading and sharing light on my post. Yeah, unfortunately this is a universal issue. Let’s keep believing and do all we can to make the system better or protect ourselves by getting genuine education.
      Stay bless and safe.


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