Protein not sugar stimulates cells keeping us thin and awake, new study suggests.

A new study has found that protein and not sugar activates the cells responsible for keeping us awake and burning calories.  The research, published today in the 17 November issue of the scientific journal Neuron, has implications for understanding obesity and sleep disorders.

Wakefulness and energy expenditure rely on “orexin cells”, which secrete a stimulant called orexin/hypocretin in the brain. Reduced activity in these unique cells results in narcolepsy and has been linked to weight gain.

Scientists at the University of Cambridge compared actions of different nutrients on orexin cells. They found that amino acids – nutrients found in proteins such as egg whites – stimulate orexin neurons much more than other nutrients.

“Sleep patterns, health, and body weight are intertwined. Shift work, as well as poor diet, can lead to obesity,” said lead researcher Dr Denis Burdakov of the Department of Pharmacology and Institute of Metabolic Science. “Electrical impulses emitted by orexin cells stimulate wakefulness and tell the body to burn calories. We wondered whether dietary nutrients alter those impulses.”

To explore this, the scientists highlighted the orexin cells (which are scarce and difficult to find) with genetically targeted fluorescence in mouse brains. They then introduced different nutrients, such as amino acid mixtures similar to egg whites, while tracking orexin cell impulses.

They discovered that amino acids stimulate orexin cells. Previous work by the group found that glucose blocks orexin cells (which was cited as a reason for after-meal sleepiness), and so the researchers also looked at interactions between sugar and protein. They found that amino acids stop glucose from blocking orexin cells (in other words, protein negated the effects of sugar on the cells).

These findings may shed light on previously unexplained observations showing that protein meals can make people feel less calm and more alert than carbohydrate meals.

“What is exciting is to have a rational way to ‘tune’ select brain cells to be more or less active by deciding what food to eat,” Dr Burdakov said. “Not all brain cells are simply turned on by all nutrients, dietary composition is critical.

“To combat obesity and insomnia in today’s society, we need more information on how diet affects sleep and appetite cells. For now, research suggests that if you have a choice between jam on toast, or egg whites on toast, go for the latter! Even though the two may contain the same number of calories, having a bit of protein will tell the body to burn more calories out of those consumed.”

http://www.cam.ac.uk/research/news/3pm-slump-why-a-sugar-rush-may-not-be-the-answer/#

A Doctor in Your Pocket

What does the future of medicine hold? Tiny health monitors, tailored therapies—and the end of illness

Take a moment to imagine what it would be like to live robustly to the ripe old age of 100 or more. You wouldn't die of any particular illness, and you wouldn't gradually waste away under the spell of some awful, enfeebling disease that began years or decades earlier.

It may sound far-fetched, but it is possible to live a long, disease-free life. Most of the conditions that kill us, including cancer and heart disease, could be prevented or delayed by a new way of looking at and treating health. The end of illness is near.

Today, we mostly wait for the body to break before we treat it. When I picture what it will be like for my two children to stay in good health as independent adults in 10 or 20 years, I see a big shift from our current model.

I see them being able to monitor and adjust their health in real time with the help of smartphones, wearable gadgets—perhaps like small, invisible stickers—to track the inner workings of their cells, and virtual replicas of their bodies that they will play much like videogames, allowing them to know exactly what they can do to optimize every aspect of their health. What happens when I take drug x at dosage y? How can I change the expression of my genes to stop cancer? Would eating more salmon and dark chocolate boost my metabolism and burn fat? Can red wine really lower my risk of heart attack?

From a drop of their blood, they will be able to upload information onto a personal biochip that can help to create an individualized plan of action, including both preventive measures and therapies for identified ailments or signs of "unhealthiness." (Other body fluids—like tears and saliva—might be routinely tested, too.) They would be on the lookout for problems like imbalances in blood-sugar control, a risk factor for diabetes, and uncontrolled cell growth, which could signal cancer. Their doctors won't just examine them once a year; they will continually monitor the next generation of patients, offering advice along the way.

What is equally exciting is that this patient data will be added to a universal database that can be aggregated by powerful search engines like Google and constantly fed into new trials and experiments—speeding up our understanding of which drugs work best for which people. The database might show, for example, that people with a particular genetic profile respond to one type of cancer treatment but not another. As more people anonymously add their health data, this database would become more and more effective as a tool for preventive medicine.

Today, most people who are concerned about their health follow sweeping, general guidelines. If you want to lose weight, you are likely to pick a diet that advises eating more fibrous vegetables and cutting back on processed sugar. If you want to reduce your risk for cancer, you avoid tobacco smoke, exercise regularly and take early detection seriously.

The problem with health care today is that we don't know enough about the body to practice preventive medicine actively. With limited knowledge, diagnostic medicine makes sense. If we don't know what we're trying to prevent or how best to do it, we have to wait for an obvious symptom to emerge in order to take action. At that point, we're usually treating a disease that has had ample opportunity to progress.

We can do better. To start, we need to appreciate the body for what it is: a very complex network, much of which we don't yet fully understand. When you look at the body from this systemic point of view, you begin to see that a lot of what we know about health is gravely misunderstood.

In 2009, my colleague Danny Hillis—a former Disney engineer who pioneered the development of so-called parallel supercomputers—and I set up a way to measure 100,000 different types of proteins from a single drop of blood. The goal is to evaluate and make sense of the body's intricate inner workings in a way that's much more dynamic and insightful than what DNA alone can provide. Proteins change in your body every minute, depending on what's going on internally. Our ultimate plan is to develop tests, based on protein levels, for illnesses like cancer. Such tests could take the place of invasive techniques like biopsies.

With each passing year, the technology necessary for this revolution in medicine is growing less expensive. Last week, Life Technologies of Carlsbad, Calif., announced that it will be able to map an individual's entire genetic sequence in one day, for $1,000. Similar tests today cost many thousands of dollars. The ability to follow day-to-day changes in your body's proteins and metabolites is not far behind.

So how do we get to this future?

It has to start with data collection. In 2004, Dell launched a company program called Well at Dell to encourage healthy lifestyles. Employees receive alerts and information customized to their health issues, incorporating their latest test results and treatments and allowing them to make more informed decisions. A newly diagnosed diabetic, for example, might get information about how to monitor blood sugar and watch out for the circulatory problems that often accompany the disease.

Not surprisingly, these corporate health-management tools have come under fire, with most critics worrying about privacy. But we can't expect the health-care industry to continue to innovate and grow if we continue to hoard health information.

The federal agency that administers Medicare pays over half of the medical bills in the U.S., but it doesn't retrieve, organize or mine that data. Imagine how much better the Medicare system could be if all this data were analyzed to improve public health. Or imagine databases from many different sources, private and public, coming together in a centralized network that would look for patterns and try to translate them into new ideas for anticipating and preventing health problems.

Personalized medicine isn't as far away as you might think. Consider what's already happening in genetic profiling for individuals, which is available today for several hundred dollars. I co-founded a genetic screening company and am a big proponent of the technology. It allows us to take a broad look at DNA variations and to assess your risk for certain ailments and what medications, at what dosages, might work best, based on your metabolism. Just because you have one or two markers of genetic risk does not mean that you will definitely develop a particular condition, but the outcome can be affected by changes in lifestyle, or in some cases, by taking medication.

As these and other technologies advance, it will become progressively easier to monitor and maintain our overall health. Then it will be up to us. The promise of personalized medicine depends, finally, not on the tools that become available but on our determination to be informed and willing patients.

http://online.wsj.com/article/SB10001424052970204124204577155162382326848.html?mod=djemWMPIndia_h