The short-sightedness of clinical trials

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The short-sightedness of clinical trials
The results of randomized clinical trials to test nutrients continues to grab the headlines, and more often than not the titles are not positive. Is the emphasis on a trial model anchored in drug testing a good thing for nutrition? Stephen Daniells talked to Prof Jeff Blumberg from Tufts University for this views.

Here is a direct transcription of this podcast:

Hello and welcome to this podcast from I’m Stephen Daniells. It’s never plain sailing for any industry, and the dietary supplements industry is no exception. Over the past couple of years the industry has suffered its fair share of bad weather, and much of this was due to the results of randomized clinical trials. These trials use the same design as for drug studies. I asked Jeff Blumberg, professor of nutrition science and policy at Tufts University, if such trials were suitable for nutrients, or if the results of these studies were merely a storm in a teacup.

Jeff Blumberg: “Nutrients work differently than drugs. Drugs are designed to work by themselves, and to be targeted to a very specific condition, a very specific biochemical receptor, or pathway, to treat a specific condition that already exists. ”

So what kind or research should we be looking to employ?

Jeff Blumberg: “We need to look at a broader way of employing research strategies that will really allow us to answer the questions that are really important to nutrition, and those questions are different than the questions that the drug industry is asking for how do we test the efficacy of a new chemical entity to use as a drug therapy.”

And let’s not forget to factor in just exactly how​ nutrients work.

Jeff Blumberg: “When we look at nutrients, nutrients are distributed throughout the body. Essential nutrients like vitamins and minerals have to be in every cell in every tissue in our body. But in fact the body concentrates those nutrients in higher amounts in some tissues and in lower amounts in other tissues, it uses them in combination with other nutrients. They are designed in a system of synergies and networks.”

Can you give us an example?

Jeff Blumberg: “So when we look at B vitamins for example, that are involved in one-carbon metabolism pathways to regulate DNA, for example, to develop new proteins, for example, you don’t just say ‘well, what does folic acid do?’ you have to say ‘how does folic acid work, together with vitamin B6, and vitamin B12, and betaine, and choline, and it’s how they interact that’s important. The ratio between the two and how they’re distributed in those ratios in different cells, and to look at that, and to do interventions with B vitamins, for example, requires a very different approach than that mindset for testing drugs.”

So this suggests that randomized clinical trials are not the be all and end all?

Jeff Blumberg: “I think that when we look the idea at a single gold standard, like the randomized clinical trial, for evaluating nutrients and foods and diets just doesn’t work. Sometimes it’s useful for answering for some very specific questions, but I think at other times we must go and use the approach that we have been using for the last generation or two, of looking at all of the research strategies and the information they can give us, from basic research using cell cultures and animal models, from clinical experience looking at how patients respond in the clinic, to observational studies of large populations followed for long times consuming different types of diets, as well as the intervention clinical trials.”

But with so much emphasis being placed on randomized clinical trials, especially in supporting health claims, what needs to change?

Jeff Blumberg: “We really have to go back and recognize that the way we developed recommended dietary allowances, the way we have developed dietary guidelines has not been based on RCTs, it’s been based on all of this knowledge that we have been learning, all of the studies that have been conducted over the last few decades, not just one research approach alone.”

That was Jeff Blumberg from Tufts University. Scientific research is never easy, but a bigger challenge may be in convincing the regulators of the need to consider all the science.

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