Don’t be too quick to use health related information gained through animal studies, or even from early studies on people.

I spent a large part of my life working with, and as a scientist. I appreciate the sheer hard work, drive and persistence that research science requires. And, I think that the onus of proof in science is hugely important. But, I also realise that science can never be always correct. Reading any history of science will show you how often an established scientific ‘fact’ has been discredited. Or, how a theory has been based on error.

This is not necessarily the fault of science or scientists, although scientists are certainly subject to all the human frailties. A major part of the difficulty is that science works in the area of the unknown or partly known. Which means there is always uncertainty.

Another problem is that scientists often have to build up enough knowledge to make sense of completely new things. After all, who could possibly understand the nature of relativity or quantum science without a large body of other knowledge.

Another common problem is blindness due to familiarity. What do I mean? Simply this. Most of us tend not to think too hard about what we do that is routine, unless it is a hassle. Then we try and find ways to improve it. Scientists also can fall into this trap.

And now, I finally get to the point.

I just came across a publication in a scientific journal that threw a minor bomb into areas of health research. [PNAS (2010). 107:14, 6127-6133]

The scientific publication asked one simple question- how much health research using mice and rats was valid, as by several measures, the experimental animals used are actually unhealthy.

What did the scientists mean?

The mice and rats used in most scientific studies have continual access to food and get little exercise. And they have little opportunity for mental stimulation.

These are hardly conditions that promote good physical and mental health.

The scientists compared mice kept under normal laboratory conditions with mice that had their diet restricted to a couple of meals a day, and with mice that got regular exercise (but had permanent access to food).

The mice kept under normal laboratory conditions tended to be obese and glucose intolerant. That is, the supposedly normal control mouse used in health research tended to be overweight and showing signs of metabolic disease.

For example, the laboratory mice had 25% to 40% body fat compared with 5% to 20% body fat in mice that ate less or exercised. And they had increased oxidative stress, inflammation and insulin resistance.

I’m sure that you would agree (with hind sight) that the danger was obvious. If you give animals (or humans for that matter) little exercise, constant access to food and little mental stimulation, they are not going to be healthy (normal).

There are very many implications for health research (including the pharmaceutical industry).

Here is one that the scientists suggested. Calorie restriction and longevity.

Early studies on mice and rats showed that they could live something like 20% to 40% longer if they were placed on calorie restricted diets. But, later studies on other animals and humans struggled to show this same effect. In fact, most studies showed that calorie restriction seemed to have little or no beneficial effect on lifespan for other animals and humans.

In contrast, many studies have shown that calorie restriction does have a beneficial effect on life span for obese animals and humans.

And now, it all makes sense.

Of course calorie restriction helped normal (sedentary, obese, metabolically diseased) laboratory mice live longer. But, does it help normal wild mice (active, lean, metabolically healthy mice), or healthy laboratory mice?

My guess- probably not.

In truth, I have to admit mea culpa.

I made another classical mistake. I assumed that scientists had checked the health of laboratory mice. I too was blinded by knowing that scientists had been using mice in research for a long time. I had assumed that the obvious (the health of the mice) had been investigated and accounted for in the past.

Scientists and non scientists who challenge common wisdom and accepted ‘fact’ using quality science, observation or reasoning are a hugely important part of improving our knowledge and processes.

As a final cautionary note- you have seen that mistakes can be made by scientists even though they are trained to be cautious and spend their lives learning enormous amounts of information.

They have to be careful because they know that all their work is carefully scrutinised by experts in their field and that their reputation is at stake when they publish their research.

My question is- how many more mistakes are made, and misinformation spread, by people without appropriate training and skills, and with a financial interest in what they are doing.

Another risk is that some people read scientific press releases and use the information without checking the quality and validity of the research. This occurs, even with well intentioned people.

These risks are magnified on the internet.

My advice is to tread carefully. Get advice from your doctor or other professional if you want to try anything that seems a bit radical or unusual.

Take care and best wishes from your editor

Ian

Tagged with: health research challenged

Filed under: General Health • metabolic disease • weight gain