Monday, April 25, 2011
If it was due to some underlying predisposition, I reasoned there would be true cause for concern. Some rogue genetic defect that lies in wait until the bearer unwittingly triggers it, I imagined I was one such unfortunate soul and that surely, it was a matter of time.
An argument with a colleague a few years later narrowed the argument a bit- the disease was either something that could happen to anyone, or something that could only happen to certain people. We now know that both could be true but that the latter is the more likely.
While I have always been interested in the disease, a new book reminded me of the broader ramifications of our current treatment of it. I don't mean just the pharmacological approach- that is complex enough- but also the treatment of schizophrenic individuals. In the early 80s many of the mental institutions that housed people afflicted with this and other diseases, were closed in favor of 'community based care' that basically never happened. As the institutions closed, residents had nowhere to go and many schizophrenics ended up on the streets. Once colorful character in St Louis, (where I hung my hat for a while) sat on street corners and drew what he saw. Day after day, he created fantastically detailed pencil drawings of building, people, parks, transport. He lived in a shelter during the night hours but had nowhere to go in the day. He wore no shoes, even in the depths of a Missouri Winter. One day, we heard he had been hit and killed by a car. A tragic waste of life and a talent that would be sadly missed by all who watched him as he drew.
'Henry's Demons' by journalist Patrick Cockburn, is a remarkable account of his son's experiences with schizophrenia, and he shares the writing with his son to give the reader a first-hand view of what the disease is like. Henry also didn't like to wear shoes, and he did not believe he was ill for much of the time. The onset of disease was in his early 20s, which is typical, and appeared to have been triggered by marijuana use. I was surprised to read that this is quite common with marijuana (I will post on this in more detail eventually- I am researching it now...). Henry and his family's struggle is vividly described in the book and one wonders how many similar stories are out there. Patrick speaks about the need for institutions for those that cannot exist without such a structure, particularly when they are deep into their illness. I wondered how people in the US coped with the costs of the treatment and care and then I remembered. Many of our schizophrenics are homeless and penniless. I have met them while working at my local food bank. They can appear normal for a while, but not long enough to hold down a job. They can't just pull themselves together because they are confused about who they themselves are. They see the world from a unique perspective and Henry and Patrick's story is a remarkable insight into that perspective. I recommend it.
Wednesday, April 13, 2011
Hormones are necessary chemicals that circulate in the bloodstream to keep our bodies running smoothly. They regulate all bodily functions including sleep, sex-drive, moods and appetite although the precise mechanisms of their actions is imprecisely understood, and becomes perhaps more so as we gain more knowledge of all the moving parts. In recent years, the hormone leptin acquired a certain mystique for its potential role in the regulation of appetite. Leptin reduces appetite but its effects are complex and people who are overweight or obese may become resistance to its actions. The hopes of drugs to modify leptin have been somewhat confounded by the complexity of the system but new hope has arisen since the discovery of ghrelin, a hormone that acts as leptin's counterpart by stimulating appetite under certain conditions. Ghrelin is considered to be the first circulating hormone that stimulates hunger. It is increased before a meal and decreased during the meal so that as a person becomes full, the hormone levels drop and appetite is suppressed.
Ghrelin's action is also very complex but a study released today by the Journal of Neuroscience (April 13th issue) provides an interesting new piece of data. It seems that ghrelin enhances the sense of smell, causing rats to sniff more often and smell more intensely. The investigators suggest that this may be an important mechanism to help animals find food when they are hungry. When humans were given ghrelin in the same study, they inhaled air tainted with various 'flavors' more deeply than without ghrelin. There was no difference, however, in how much they like the smells after ghrelin. It seems ghrelin may make us more aware of potential foods around us but the effects of its evolutionary advantage in over-fed humans is not well understood. Evidence does suggest that ghrelin plays a key role in appetite regulation along with the other hormones, insulin and leptin. The big questions that may help us understand how to use these data to address the current obesity epidemic revolve around how to seperate our physiological drives to eat from the psychological ones. David Kessler, former FDA commissioner, has suggested that the Western diet itself alters our body's ability to regulate our appetite and our food intake and these hormone likely have a critical role. Once we get into the vicious cycle, it takes heroic efforts to break out of it. With high calorie, processed food being cheaper and more accessible than more nutritious fare, it seems the odds are stacked against us.
As we understand more about the effects of particular foods on our responses to these 'hunger' hormones, perhaps we will find the evidence we need to regulate food production more appropriately so nutritious foods are more widely available at reasonable cost. In the meantime, yet another study has shown that sniffing a certain food can actually decrease our appetite. In women, just the smell of dark chocolate suppresses appetite and interestingly, it appears to be accompanied (or preceded?) by a change in circulating ghrelin in these subjects.
Even with all the uncertainties of the system, it does seem that exercise and a reduction in calorie intake both work together to move the regulatory effects of leptin, insulin and ghrelin in a favorable direction. So in other words, we can't go wrong if we walk a little more, eat a little less, and take a whiff of dark chocolate now and again.