Michael Mosley’s latest attempt at popular science airs on
the BBC this week as part of the Trust Me I'm a Doctor series. http://www.bbc.co.uk/news/magazine-33601171 This time he is investigating different diets for
lowering cholesterol. The program looks serious and appears to employ a reasonable but
limited experiment comparing three different diets using a randomly allocated sample
group and then observing the effect of each on total cholesterol levels.
One
of the diets was a low cholesterol diet, any yet we have
known for a long time that dietary cholesterol has very little impact on
blood
cholesterol, in fact the US Dietary Guidelines Advisory Committee
recently removed it from their list of bad things to eat! A second group
ate high fibre diet as fiber binds with cholesterol
in the gut and stops it getting absorbed; this is even dafter as the
premise is
still based on the role of dietary cholesterol. The third group added
nuts to
their normal diet; this approach is known to lower cholesterol.
Mosley then trumps the lot with a "Portfolio" diet where he
creams off the best bits of each diet, adds some other changes and lowers his cholesterol by more than the
guinea pigs.
But
here’s the thing. Total cholesterol is almost
meaningless number when it comes to risk of heart disease!Why? Because
it includes the "good" HLD cholesterol, and apparently the more of that
we have the better. And because the role of LDL is misunderstood.
Mosley then quotes some out of date information on LDL cholesterol from
the NHS Choices web site which still maintains that Total LDL is the enemy,
despite consistent evidence showing that there is practically no relationship
between total LDL and heart
disease. Heart surgeons have been pointing this out for decades but they have been silenced by the makers of statins.
Why, oh why couldn’t Mosley have done a bit more research
and looked into the fact that LDL particle size is the real culprit? Smaller
LDL particles are more dangerous and larger ones are safe, and hence their
total mass is of no consequence.
He could then have made the quantum leap back
to his favorite subject of diets and announced to the world that high-carb
diets promote small LDL particles and high-fat low-carb diets promote larger
safer LDL particles.
Missed again Michael!
In fact I ought to say "Missed again BBC!", I am amazed by the low quality of the science provided on the BBC when it comes to the subject of diet and obesity. There are dozens of top scientists who understand the subject infinitely better than Michael Mosley does, but the BBC's commissioning editors do not appear to be interested in discovering the inconvenient truth that the NHS's advice on cholesterol and heart disease might be wrong.