Monday, May 05, 2008

Wonderful, Cosy, Feel-Good, NATURAL Chemicals

According to The Sydney Morning Herald, Louise Hall is a "Health Reporter". According to The Age, she's just Louise Hall. I guess "Lazy Hack from Sydney" doesn't look too good as a by-line when you're syndicating crap written by an interstate colleague. But let's not turn this into a Melbourne vs Sydney, Age vs SMH thing - The Age has one or two notably lazy hacks of its own, like this humourless humourist.

With the help of promotional material from Galen Naturopathic, Hall reports a surprising discovery:

FEELING blue? Mung beans, lobster, turkey, asparagus, sunflower seeds, cottage cheese, pineapple, tofu, spinach and bananas could lift your spirits.

It's easy to see how tucking into a lobster bisque or a turkey sandwich might make you feel better if you're feeling a bit glum - eating tasty food is a pleasant activity. The mung beans and tofu are a bit of an odd inclusion but there are people out there who like both - sometimes on the perverse basis that there's something virtuous about eating bland food to preserve the buff temple of your personal narcissism - so once again, the intrinsic pleasure of eating stuff you like might be the reason you'd experience a lift in spirits. According to Galen Naturopathic, via Hall, you'd be wrong to take such a naive view:

A diet high in tryptophan — an amino acid converted by the body into the feel-good chemical serotonin — can improve mood and wellbeing, a pediatrician and natural health expert, Caroline Longmore, said.
When and where did Longmore say this? Probably in a press release, such as this, where Longmore is described as "a French ex-paediatrician who has run Galen Naturopathic Centre in Richmond upon Thames for the past five years". Or in a spam e-mail to the world's Health Reporters.

The body cannot produce tryptophan so unless we get enough through diet, we may suffer a deficiency, leading to low serotonin levels, which is associated with mood disorders, anxiety, cravings and irritable bowel syndrome.

"Following a diet which contains foods rich in naturally occurring serotonin will improve your mood, leaving you energised and in a state of harmony and wellbeing," Dr Longmore said...
So Dr Longmore - a former paediatrician turned naturopath, proprietor of a naturopathy clinic named after the ancient Greek physician who is credited with holding back western medicine for more than a millenium - is spruiking a fad diet with Hall's eager assistance.

Right up to that last paragraph, neither Longmore nor Hall had put a foot too far wrong on the basic science too. Tryptophan is an essential amino acid which we have to get through diet - it's one of several such amino acids. And it is the biochemical precursor to the "feel-good chemical serotonin". It's just the spin that Longmore - through Hall - puts on those scientific facts that's a bit off.

The claim that "following a diet which contains foods rich in naturally occurring serotonin will improve your mood, leaving you energised and in a state of harmony and wellbeing," cranks the spin up by quite a few revs. Longmore's implied argument is that eating more tryptophan will lead to more serotonin synthesis and since we know that low levels of serotonin in certain parts of the human brain are associated with major (or clinical) depression it follows that eating lots of lobsters is going to be just as good for you as those nasty, big Pharma produced SSRIs. Not too long after the spin comes the outright bullshit:

In her e-book, The Serotonin Secret, Dr Longmore claims the best way to get optimum tryptophan levels is through a carefully devised eating plan.

She rates dozens of foods for their levels of tryptophan. Written with an Australian-trained medical scientist and naturopath, Katrin Hempel, the book has 50 recipes designed to solve serotonin imbalance without drugs. The concept works on the same principle as selective serotonin re-uptake inhibitors, such as the popular antidepressant Prozac.
No it bloody well doesn't. The concept works - to gull people into buying copies of Longmore and Hempel's book - by misrepresenting science. To explain this, I'll have to take a short detour into some basic concepts of modern pharmacology.

First up, pharmacology doesn't interest itself in the origin of drugs. Morphine is a narcotic analgesic derived from opium poppies. Pethidine is a synthetic narcotic analgesic introduced into use in 1939. The two drugs are classed as narcotic analgesics because they produce the same effects - narcosis and pain relief. They've also been found to work on the same receptors in the nervous system.

A basic assumption of pharmacology - one which I doubt has been discarded in the few decades since I studied the subject at university - is that drugs (however defined) achieve their effects by either imitating the action of chemicals that naturally occur in the body (such as hormones and neurotransmitters) or by interfering with natural responses - at the cellular level - to those naturally occuring chemicals. This occurs because the drug binds to one of those receptor things, and either triggers a response, or hangs around doing nothing, like those boofheads who always plant themselves in doorways at parties.

SSRIs - Serotonin Specific Reuptake Inhibitors - are like the aforesaid boofheads. They block molecular "doorways" that take serotonin back into nerve cells after its release. The result is that the serotonin hangs around the synapse (the microscopic gap between one brain cell and another), long enough to have its "feel good" effect. But let's remember that it's only in the brain, and very specific sites within the brain where we want this happening. SSRIs are used in the treatment of clinical depression because they're very good at hitting that site. And because they've been tested and shown to work in clinical trials.

Raising your tryptophan intake because a former paediatrician tells you that it will lead to an increase in "feel-good" serotonin is a very different proposition. There's no evidence that it will work and quite a few reasons to think that it won't.

Making serotonin isn't the only use your body has for tryptophan. As an essential amino acid, tryptophan is also used in protein synthesis. So there's no guarantee that the extra tryptophan will get converted into "feel-good" serotonin. Neither is there any guarantee that extra serotonin production will happen in the brain - serotonin plays other roles in the body. It's present in blood platelets - when platelets bind to wounds to stop bleading, serotonin is released into blood vessels and constricts them.

At most, it might work, and if your tryptophan enriched diet includes a lot of those lobsters, turkeys, pineapples and bananas, you'll definitely have reason to feel good. You might even feel clever about boosting your serotonin levels, but you'd be fooling yourself; harmlessly, if your problem is merely "the blues" and you need a bit of a pick-me-up, not so harmlessly if the problem is more severe.

Hall finishes with a bit of token balance (there's more token balance earlier in the piece):
Britain's Food and Mood Project recommends eating chicken, sardines, turkey, salmon, fresh tuna, nuts and seeds to boost serotonin levels. But Associate Professor Michael Baigent, clinical adviser to the BeyondBlue anti-depression organisation, said there was only low-level evidence to suggest tryptophans had a medical effect.

Statistics show that in any 12 months, almost 17% of adult Australians have a mental disorder, with anxiety, depression and bipolar the most common.

In February, a major international review of clinical trials of new generation drugs, including Prozac and Aropax, found they were no more effective than a placebo, or sugar tablet, for most people with depression. (My emphasis there, to ensure you didn't miss the token balance)

That last paragraph isn't included in the SMH's version of the article - it most likely refers to the paper by Irving Kirsch et al where the conclusions were consciously spun by the paper's author to suggest a conclusion that was in fact refuted by the study's own data and data analysis.

Hall's article is a gift to Galen Naturopathic and to Australia's cray fishers, turkey farmers and growers of pineapples and bananas. But those 17% of Adult Australians with "mental disorders" have nothing to thank her for. Especially those who'll be hearing from friends and family that they need tostop wasting their time with the pills and get a bit more crayfish in their diet.

4 comments:

Lord Sedgwick said...

Ponder this Gummo.

Outside most of the major metropolitan race courses there was always (and still may be) a van selling crayfish.

I always thought it was there so you could splash out on a bit of posh nosh from yer winnin's - and to placate the missus who didn't know where you were, but having read that it would seem these purveyors of crustacea were serving a therapeutic function for chaps like me ((to quote from the great poet Paul Anka's magnum opus 'My Way', "Ive had my fill; my share of losing") who were felling a bit down after having missed out on backing the winner (always by a short half head or an unjustifiabily upheld protest) in the last race

Jacques Chester said...

Good treatment of the topic. The key word in SSRI after all is "Selective".

It does upset me that there's a backlash against SSRIs generally. Depression is a dangerous disease and not something to treat by halves.

Speaking only for myself, zoloft has been a godsend. Positive thinking and turkey aren't as effective as my daily dose of sertraline hydrochloride.

drwoood said...

SSRI's are not as selective as they claim to be. Many of them also interact with other monoamine trasnporters, and may bind (or block) individual serotonin receptors to a lesser degree. We should also remember that there about 14 different types of serotonin out there, an increase in serotonin synapse levels may affect all 14 of these receptor subtypes. Maybe the extra S in SSRI should stand for 'spin'.

Gummo Trotsky said...

drwoood,

I presume you meant to say that there are 14 different types of serotonin receptor out there.

No drug is entirely specific in its actions, which is why so much effort is put into identifying and documenting non-therapeutic side effects, as well as the beneficial actions. It's also why doctors who prescribe any drug over a long term check out their patients for those adverse side effects.

Maybe you should try to actually argue your case next time you comment.