The Facts And
Fads Of Healthy Eating
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New
research suggests that doctors may needlessly vilify cholesterol and demonise
fat
Each time I come across
an interesting bit of news about food and health, I write about it. If you’ve
been following my health articles, you will know that they follow two basic
trajectories. One: foods that may not necessarily be very good for you, such as
milk or gluten. And two: the links between heart disease and the food we eat.
It’s the second strand
that intrigues me this week. Ever since the turn of the century when The New
York Times
Magazine ran a now famous
cover story, we have all been grappling with the idea that decades of medical
orthodoxy may be founded on a misconception – that fat is a villain and the
enemy of good health.
The survey that The Times
quoted in that influential article suggested that fats may not cause heart
disease or even be bad for you. Such was the impact of the story that protein
and fat-rich diets such as Atkins began to soar in popularity. A second finding
of the research – that carbohydrates caused obesity – became nearly as
influential. In much of the West, people gave up on bread and rice, preferring
such newly-rediscovered grains as quinoa. (Actually quinoa is not really a
grain in the traditional sense, it is a protein that people use as a rice
substitute.)
Over the years, both of
those conclusions have been reinforced by more and more research. In America,
they now trace the epidemic of obesity back to a notorious government
recommendation that urged people to eat less meat and more grain. You don’t
need to be a scientist to work out that the fattest Americans tend to be those
at the bottom of the socioeconomic ladder who eat lots of wheat-rich
(hamburgers, pizza, sandwiches, etc.) foods.
(It always intrigues me
that, in body-size terms, America is the opposite of the Third World. Here, if
somebody is very thin, it often means they are poor and can’t afford enough
food. In America, the rich stay thin while 2 the poor get fat.) Another US
government recommendation kicked off the global craze for olive oil. Americans were
told that saturated fats (basically, any fat that turns solid when cool) like
butter were the enemy and that olive oil was good for you. Till that point,
olive oil had been preferred for its taste. Now, people spend three or four
times the amount they would spend on normal oil to buy olive oil in the belief
that it would keep their hearts healthy.
Doctors even used olive
oil to explain the so-called French paradox. If meat was so bad for you, people
wondered, then why did the French – who eat lots of red meat – have relatively
low rates of heart disease? Ah, easy to explain, said the nutritionists. They
cook in olive oil and olive oil contains substances that sweep through the
arteries clearing plaque and widening them.
This sounded miraculous
till you realised that the parts of France with low rates of heart disease were
located in the North where they prefer to cook in lard and butter and not in
olive oil. (In any case, the evidence for the French paradox itself, now seems
to be fading.)
Over the last decade,
studies suggest that the basis for the medical establishment’s hatred of fats
(and especially animal fats like butter) is fundamentally flawed. Last year,
the US government conceded that there was no direct link between dietary
cholesterol and cholesterol levels in the blood. Till then, doctors had
believed that if we ate cholesterol-rich foods, this cholesterol would show up
in our blood. Now, they accept that our bodies do not work in such a simplistic
way.
The fat-is-poison
orthodoxy suffered another blow two months ago when researchers from the US
National Institutes of Health, the Mayo Clinic and the University of North
Carolina published a paper suggesting that even in the 1970s, doctors should
have known that the anti-fat orthodoxy was flawed. (There is an excellent
article about this by Katherine Ellen Foley in Quartz, from where I’ve gleaned
much of this information.)
Researchers looked at the
raw data of a study that ran from 1968 to 1973, which followed the diets of
9,750 men and women. Some of those who were part of the study ate meals made
with animal fats (butter, for instance) while others ate food cooked with olive
oil or vegetable fats.
The research showed that
those who used plant fats had 14 per cent lower cholesterol overall. But, surprisingly,
the people with lower cholesterol had higher risks of death than those who ate
animal fats! For every 30 points that cholesterol went down, the risk of death
actually increased by 22 per cent. (This is a statistical study so it only
tells you what happened, not why it happened.)
So does that mean that
the received wisdom about cholesterol and the risk of death is wrong? Well, may
be. Most of us have been brought up on a plumbing model of heart disease.
According to this model, your heart is a big pump and the arteries are the
pipes that lead out of it. If these pipes are clogged, it leads to heart
disease. The problem with cholesterol or any fat in the blood, we are told, is
that it functions like grease and clogs up the pipes, narrowing the flow of
blood. And when the flow is restricted, you get a heart attack.
This model is not
necessarily wrong. It is just oversimplistic. And the bit about grease blocking
the pipe is particularly misleading. In April, researchers from the UK and the
US reviewed all the existing studies about cholesterol and heart disease. Their
conclusion was that these studies proved that “the conceptual model of dietary
saturated fat clogging a pipe is just wrong”.
Heart disease is caused
by inflammation. And various factors could cause that inflammation. Blood
cholesterol is not entirely blameless. There can be tiny cholesterol bubbles
inside the arteries and they could cause heart attacks when they burst. But
what makes them burst is still not clear.
What we do know, however,
is that another spoon of ghee will not cause the cholesterol bubbles to burst.
The researchers found that in every study they looked at, the lowering of fat
levels in diets did not reduce the incidence of heart attacks, strokes or
coronary disease itself.
So, what should we, as
Indians, take away from all this research? I am no doctor. But speaking as a
layman who likes reading up on this stuff, here are some tentative conclusions:
Don’t waste money on
expensive oils unless you actually like the taste. Olive oil is the subject of
huge scams (which I wrote about here a few years ago) revolving around its
origin and virginity. It is not clear that it helps greatly in reducing heart
disease. And in any case, there are many cheaper oils with many of the same
properties as olive oil.
Don’t get too bothered if
doctors start telling you to give up red meat. This may make sense in America
where beef has a high fat content but in India, chicken often has more fat than
our goats. And you are better off eating goat meat (which is usually free
range) than nasty industrial broiler chicken.
Statins are a
controversial medical subject, so you should probably listen to your doctor and
not to me. But here’s what I do know: the obsession with blood cholesterol
levels is falling out of favour in modern medicine. The market for statins used
to be $20 billion till recently. But after the American Heart Association put
out guidelines suggesting to doctors that they prescribe them less, the market
has dropped to $12.5 billion.
None of this is to
suggest that you should give up eating rice or rotis and gorge on butter. If
there is one thing I have learnt after years of seeing scientists change their
minds, it is this: ignore the fads. The basic Indian diet was always okay with
the possible exception of sugar (we may eat too much of it).
So pay no attention to
the same people who once told us to use vanaspati (which is really bad for you)
instead of ghee (which is fine), who try and control our red meat consumption
and who shove too many expensive medicines down our throats.
Minimise your fast food
intake and eat simply and eat well. That, and a little exercise, should be
enough to keep you going.
Vir Sanghvi BR 23JUL17
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