Why human, not mice, studies are the most appropriate for judging the effects of diet on human health

I’ve said before that while I don’t believe any one diet is ideal for everyone, I favour diets lower in carb and higher in protein (and also fat) than the diets traditionally recommended as ‘healthy’. Such diets generally give better results for weight loss than, say, low fat diets. They also tend to be extremely useful in the management of diabetes and metabolic syndrome. Also, even for those not afflicted by these conditions, they usually lead to changes in physiological and biochemical parameters that are associated with a reduced risk of heart disease such as lower levels of blood sugar and blood fats (triglycerides) as well as higher levels of ‘healthy’ high density lipoprotein (HDL) cholesterol. In my view, anyone with a special interest in the field of nutrition would have to be unaware of the research or choose to ignore it not to admit to the broad merit in lower-carb eating for human health.

Notice I put ‘human’ in the last sentence because this week saw a study which appears to call into question the safety of low-carb diets that was actually performed in mice. You can read about this study on the BBC website here. In this study mice which have been bred to be particularly susceptible to atherosclerosis were used (atherosclerosis is the ‘furring up’ process in the arteries that can lead to heart attacks and strokes). The mice in this experiment were fed one of three diets. The diets were:

1. Regular mouse chow
2. A diet comparable with a standard ‘Western’ diet in terms of fat and cholesterol
3. A lower-carb, higher protein diet containing levels of fat and cholesterol comparable to diet 2

The study, which went on for 12 weeks, found that the Western diet produced 9 per cent more atherosclerosis than the regular mouse chow diet. The lower-carb, higher protein diet, however, appeared to give even worse results (15 per cent higher than the mouse chow diet).

Not surprisingly, this study has been covered with a ‘low-carb diets are bad for the heart’ sort of message. Some researchers have tried to ‘prove’ this over the years, despite overwhelming evidence which shows that, if anything, lower-carb diets superior for cardiovascular health. Unable to find any decent human data to support the concept that low-carb diets are unhealthy, it seems some researchers will go to extreme lengths to demonstrate supposed hazards in animal models.

This study appears to be an example of this. It is vaguely reminiscent of the studies performed decades ago in which rabbits fed stacks of cholesterol were found to develop atherosclerosis. But rabbits are herbivores, and don’t have cholesterol naturally in their diet. No wonder, then, that feeding it to them in excess might not do them much good.

Mice are ostensibly herbivorous too, and by virtue of that eat a diet rich in carbohydrate. Feeding them a low carbohydrate is therefore taking them far away from the diet they are best adapted to, especially if it offers super-high levels of protein (45 per cent of calories) that mice would not be accustomed to eating. Come to think of it, humans are not be accustomed to eating such a protein-rich diet either.

Seems to me, then, that these researchers chose an inappropriate animal model to test their theory on, and then fed the animals an inappropriate diet to boot. These actions suggest that the researchers were doing what they could to design an experiment to produce a desired outcome. We get a little sense of that when it is revealed that the researchers decided to investigate their [low carb diets] impact on the cardiovascular system after hearing of reports of people on the diets suffering heart attacks. I wonder whether it ever occurred to these researchers that legions of people are dropping down dead ever day while following low-fat diets. Perhaps start here?

You can see from the article that I’ve linked to, that lead researcher Anthony Rosenzweig said the findings were so concerning to him that he decided to come off the low-carb diet he was following. I see, so this scientist has decided to turn his back on a huge stack of human evidence on the basis of one quite inappropriate animal study. The fact that it was his own study does not mitigate against the fact that this seems like a really dumb decision on his part.

References:

1. Foo SY, et al. Vascular effects of a low-carbohydrate high-protein diet. Proceedings of the National Academy of Sciences Epub 24th August 2009

10 Responses to Why human, not mice, studies are the most appropriate for judging the effects of diet on human health

  1. Jake 29 August 2009 at 1:34 am #

    I think that it was highly unethical to feed a diet to a mouse genetically programmed to die from that diet. There seems to be a lack of ethics in most nutrition researchers.

    In the meantime, their “research” is repeated verbatim by our irresponsible media and is causing needless death and disease. Lucky for us there are people like you Dr. Briffa to inform us of people like Anthony Rosenzweig.

  2. The other (non-dietician)Kate 29 August 2009 at 11:32 am #

    I have MS and in the last two weeks or so, there have been two news items about possible ‘cures’ for MS using mice.
    One involved Lisinopril, an old ACE inhibitor. I read a little more and discovered that Lisinopril ‘cured’ a disease called EA which resembles MS – but in mice.

    I have actually taken Lisinopril and it did help to regulate my hypertension but gave me the most awful cough. As I also had MS at that time, but didn’t know it, it didn’t cure it. I still had numbness and balance problems that were unexplained at that time.

    Mice are not people and people are not mice. It’s time research scientists realised this.
    As for the researcher Anthony Rosenzweig deciding to stop using his low-carbohydrate diet to control his cholesterol, that’s his choice.
    It most certainly isn’t going to stop me, a woman of child-bearing age from eating this way. That’s because I’m a woman and not a mouse.

  3. M. Cawdery 29 August 2009 at 1:05 pm #

    A similar study was done in rabbits many decades ago. Same result; same criticism.
    What gets my goat is that this sort of study in inappropriate animals is often used when the result supports the so-called consensus; in this case “fat is bad for you”

    However, statins have regularly been shown to be carcinogenic in rodents but this result is discarded because “rodents do not replicate human response”

    A typical “have your cake and eat it” response

  4. Alannah 29 August 2009 at 5:38 pm #

    Does this mean we can ignore the notorious “test de souris” on oysters in France?

  5. Robin 29 August 2009 at 6:26 pm #

    The Other Kate,

    Go here – you might find it interesting:

    http://www.second-opinions.co.uk/ms.html

    Robin

  6. Hilda Glickman 29 August 2009 at 11:07 pm #

    It depends on exactly what they ate on each diet. Was the low carb full of hydrogented fat or processed oils? If so that might have made the difference.

  7. Jenna 31 August 2009 at 3:18 am #

    http://www.bakeryandsnacks.com/The-Big-Picture/High-carb-diet-could-aid-slimming-Study

    Just wondered what your views are on the above study!

    Personally my weight has fluctuated enormously ever since I started a low carb diet. When I first put my self on the ‘atkins’ diet (ignorant) for health reasons I lost a huge amount of weight and felt so happy with myself, and found a self confidence that I haven’t found since. I felt so good, but during that time I lost my periods; I had developed anorexia. I then started to binge eat and felt I was going mad, I had to drop out of my university course. I was 18 when I started the diet. I am still suffering as a consequence, I believe that this diet/dieting has destroyed a would be natural, and healthy instinctive relationship to my bodies needs and rhythm. This whole period of time has been highly destructive in my life, it has impaired my growth in more ways than i can describe here. It is very difficult knowing what to do now as the only time i now associate with feeling good about myself and my body as a whole was when i first started to diet. After trying many different diets to get to a place where i feel ok once more I fail. Food has become a central issue in my life where other more essential matters in my life have fallen by the wayside, neglected. I am now 22 and I have spent 5 years with fluctuating body weight/depression/self worth/diet. There is so much conflicting advice, and on the most part I find all of this highly dogmatic, it does not act as a guide to ones well being, because the professional is always touted as the one to whom we need to seek advice, and I am the commodity. Now i’m finding that I must follow myself and connect my mind and body rather than someone else’s abstract chatter and my body’s needs; i’m the only person who I can trust to know and believe in. Why is it that historically tribal people have known the inherent effect of a food on the human body without ‘scientific’ studies and the like, because they observe themselves and how they themselves react to their food source. They are themselves in tune with their environment, the inherent nature of themselves and food produce. I have decided that low carb diets are absolute nonsense, I think it is not environmentally sustainable, it is a selfish need in the west, a self serving bias; my sister is currently living with ethiopian tribes and they are very lithe, they eat a high plant diet, a little meat/milk, and they are healthy, though they are unable to spend their time choosing what to eat because food is difficult to come by. Hearing what these people are struggling with on a day to day basis, for survival, makes me see just how ultimately self centered I have been. In no way have I considered the destruction that such a diet would be having not just on me, but on the environment/people as a whole. I think it is actually gross that we promote a diet that is not about preserving human populations and the environment. When we know that fish stocks are running low, the waters are becoming more and more polluted, our animals and lands neglected and poisoned all to be consumed, and mean while millions are starving because of the direct effect of our consumption, greed, and rape of the planet; at what point are we going to start thinking of the health/value of those other objects in the background; those dots beyond dots we fail to acknowledge as relevant or of value in ‘our’ lives? I think that it is time to wake up; who want’s to be a commodity?

  8. The other (non-dietician)Kate 2 September 2009 at 2:07 am #

    Robin – it is. I actually wrote to him and he answered!
    I prefer a Paleodiet and stay away from gluten and pulses wherever possible.
    Seems to work okay.
    Atkins is probably best for my lipid profile, but I prefer Paleo.

    My symptoms are under control with that and I look and walk fairly normally. Lots of fish oils and olive oil help too, I think.

    And just to buck the trends, I take beta-interferon and LDN. You have to throw everything at MS. It’s all about staying well.

  9. Trinkwasser 11 September 2009 at 11:24 pm #

    I just linked to my two favourite takedowns of this study

    http://trinkwasser.wordpress.com/2009/09/11/are-we-not-men-no-we-are-apo/

    No doubt more will be along shortly, but between them Peter and Michael Eades and their contributors have done an excellent job.

Trackbacks/Pingbacks

  1. Are We Not Men? No We Are APO « The Hypocritic Oath - 11 September 2009

    […] John Briffa just had a go also. […]

Leave a Reply