Memory-foam mattresses are the fastest-growing category of mattresses, but for some buyers, there’s a tradeoff….

You’d like to do something— anything —to speed up your metabolism, but it’s out of your control. Right? Not quite. Although genetics and your age both play a role, recent studies suggest you have plenty of say over how well your metabolism—which involves your body’s ability to break down food into usable energy—functions. In fact, you can all but negate the metabolic slowdown that happens after 40 by tweaking your diet, exercise, and sleep habits. “Think of your body as an engine—your metabolism is the rate at which your engine runs,” explains Scott Isaacs, MD, an endocrinologist in Atlanta and author of Hormonal Balance: How to Lose Weight By Understanding Your Hormones and Metabolism . “By making adjustments to these three elements, you can actually make your engine rev higher.” The eating and exercise plans on these pages were designed to keep your metabolism humming to the tune of up to 10 pounds off in 21 days. Read on for the keys to not only losing, but losing for good. Key 1: Eat early Your basal metabolic rate—the number of calories your body burns at rest—is based on things like age, height, and body type, so there isn’t much you can do to alter it. But there is a lot you can do to change the number of calories you burn above that, beginning with your diet. Specifically: Eat breakfast. We already know the reasons you may not want to (you don’t have the time/energy/stomach for it), but leaving for work on an empty stomach is like hitting the pause button on your metabolism. Here’s why: When your brain senses your stomach is empty, it sends a message to your cells to conserve energy in case another meal doesn’t arrive. In other words, your body holds onto the fat stored in your cells instead of helping you burn it off. “Breakfast triggers a process called thermogenesis, where the body signals the brain to activate the metabolic process of turning food into energy,” says Mark Hyman, MD, author of The Blood Sugar Solution . Key 2: Eat often To keep your metabolism humming, Dr. Hyman suggests eating small meals every three or four hours. Aim to make each of those meals at least one-quarter protein—whether it’s animal protein, beans, or dairy, says Marissa Lippert, RD, who designed the eating plan on page 39. A recent study in the journal Neuron suggests that consuming protein stimulates the cells responsible for switching on the body’s calorie-burning mechanism. Foods high in sugar and processed carbs, on the other hand, can lead to another problem: insulin resistance. “As we get older, it’s crucial to pay attention to how much sugar we’re consuming,” says Diane Kress, RD, author of The Metabolism Miracle . “Too much messes with your metabolism by causing your body to store extra calories as fat.” Next Page:  Key 3: Sweat off the weight Key 3: Sweat off the weight Even more important? Exercise. “Not only does it affect your metabolism while you’re doing it, but research shows you can keep burning calories up to 24 hours after you finish because your metabolism stays elevated,” Dr. Isaacs says. That’s especially true if you challenge yourself: A new study in the journal Cell Metabolism suggests that intense bouts of exercise can “turn on” genes responsible for energy metabolism. Researchers found that the activation of these fat- burning genes was higher in cyclists who pedaled at 80 percent of their aerobic capacity versus those who did a more moderate cycling session at 40 percent. So although you can’t permanently change your DNA (if only!), experts say exercise can fire up certain genes that initiate the fat-burning process. Exercise is particularly helpful once you pass the age of 40, when your metabolism naturally begins to slow down. Experts used to believe it slowed due to an inevitable loss of muscle mass. However, a study in the journal The Physician and Sports Medicine found that fit women ages 41 to 81 who continued to exercise four to five times a week as they got older had little change in body composition. The real reason you lose muscle with age? You stop using it. “We now know that women who keep up a regular vigorous fitness routine don’t experience the metabolic decrease,” Dr. Isaacs says. Key 4: Sleep away the pounds No, it’s not your imagination. Too little sleep can cause you to gain—and not just because you’re spending those extra waking hours in front of the TV nursing a bag of chips. Research suggests that people who sleep two-thirds of their usual amount (five hours instead of eight, say) eat an average of 549 extra calories the following day without realizing it. Experts believe this is because too few zzz’s upset the balance of important appetite-regulating hormones. But that’s not all: A Swedish study found that even one night of disrupted sleep can cause the body to burn up to 20 percent fewer calories the following day. “Sleep deprivation impacts multiple hormones related to metabolism,” Dr. Isaacs says. “Resistance to leptin—a hormone that regulates body weight—increases, while levels of ghrelin, a hormone that signals to your brain that you’re hungry, also increase.” Aim for seven to eight hours of pillow time a night, advises Dr. Hyman. “Just a small change in your sleep schedule can make a big difference in your health.” Not to mention your ability to burn calories.

Sleepwalking affects 3.6 per cent of adults in the U.S., more than previously thought, according to a new study that estimates the lifetime prevalence is nearly 30 per cent.

You can count me as one of the 30 percent of people who don’t get enough sleep every night, so when Lark sent me their silent alarm clock ($100) to test a couple months ago, I was all about it. Since then, I’ve been using it pretty regularly, here’s what I think of the alarm clock. First, here’s what it is: The Lark is part app (compatible with iPhone, iPod Touch, or iPad only at the moment, but an Android version seems imminent ), part motion-sensing wristband that vibrates to wake you up and tracks your sleep quality throughout the night. It promises to both help you wake up more naturally and without disturbing your bedmate and change your personality from sleep-deprived night owl to well-rested morning lark. Included in the package is the Lark sensor, wristband, and charging dock where you plug your wristband into when you wake up – both to shut off the vibrating alarm and ensure that your wristband has enough juice to monitor your sleeping stats for the next night. The charging dock includes a USB port to connect your iPhone charger to it, so you don’t have to use two sockets for each. Who it’s for: The Lark is useful if you have a partner and you both wake up at different times. Since it’s a silent alarm clock, it rouses you with a series of vibrations through your wristband, so if your normal wake-up call is earlier than your bedmate’s, your partner can snooze away without being disturbed. That may or may not be valuable enough for you to justify the $100 price tag, but it is an effective solution. Besides the alarm clock portion, the Lark app tracks several sleeping stats: how many hours you slept as well as how many times you woke up during the night and how long it took you to fall asleep (both based on your movements). Keep reading for my thoughts on the Lark alarm clock.

Here’s what’s making health news this morning: Are You Mom Enough? (Time): Featuring a provocative cover photo of a mother breast-feeding her three-year-old child, the magazine explores attachment parenting. Its three main tenets are extended breast-feeding, co-sleeping and “baby wearing,” in which infants are physically attached to their parents by slings.

A mismatch between when our internal clock wants us to wake up and when the alarm clock rings to get people to work and school on time could be fuelling obesity, a European study suggests.

The artist Thomas Kinkade, 54, died in April from a lethal combination of alcohol and Valium, according to an autopsy report from the Santa Clara County, California , medical examiner. Alcohol and Valium, also known as diazepam, are both depressants that slow down the central nervous system. These depressants slow down the brain and also decrease the heart rate, lower the blood pressure and cause lethargy. “Because your brain will control autonomic function like heart beat, breathing, when the concentration is so high that area of the brain is affected, it does not function,” said Douglas Rohde, supervisor of chemistry and toxicology at Lake County Crime Laboratory in Ohio .  Rohde is not involved in Kinkade’s case. This could knock a person into a coma, and then breathing and heart beat could stop. Kinkade’s autopsy report cited "acute ethanol and diazepam intoxication" as the cause of death and the manner of death "accidental." When the two substances are combined, the alcohol heightens the effects of Valium. This drug is a benzodiazepine, a widely prescribed type of medication. It's prescribed for sedation, sleep and relief from anxiety and muscle spasms.  The drug comes with warnings about alcohol use. “When the patient mixes alcohol plus Valium, often times the effect can be greater than those alone,” said Bruce Goldberger, professor and director of toxicology at the University of Florida Medicine .  “This phenomenon is known as synergistic.  So 1 plus 1 is not 2, but 3 or 4, demonstrating an enhanced effect, rather than taking the drugs alone.” Deaths due to this mixture have been commonplace for decades, he added. The combination could cause euphoria, but the mix is highly risky because it, “essentially shuts down the normal processes of the brain which can lead to death,” Goldberger said. Kinkade also had heart disease, according to the autopsy. But it was not listed as a cause of death. His brother had previously told the San Jose Mercury News   that the artist had battled alcoholism for four or five years. Filed under: Alcohol , Prescription Drugs Tagged: Madison Park – CNNhealth.com Writer/Producer

Working a nine-to-fiver is mandatory for most people, and unfortunately, a long commute often comes with the territory. According to a study published today in the American Journal of Preventive Medicine , those who travel 16 or more miles each way weigh more and have higher blood pressures than those with less than 10-mile commutes. Of the almost 4,300 residents from Dallas and Austin involved in the study, researchers discovered that for every 10-mile increase in driving distance, the commuter’s BMI (body mass index) rose .17 units. People with lengthy commutes are nine percent more likely to be obese, either because they didn’t exercise as much, are eating fast food while driving, or they’re not getting enough sleep because their long commute forces them to wake up early. Weight isn’t the only thing affected by a long drive to work. Spending that much time in the car, especially stuck in traffic, also makes a person tired, moody, and stressed out, which is one reason 52 percent of those in the study with a longer commute suffered from high blood pressure. So what’s a commuter to do? Quitting your job is obviously not an option, and if working at home part-time isn’t feasible and neither is finding a job closer to where you live, keep reading to learn what commuters can do to avoid weight gain and other health issues.

Editor's note: CNN contributor Amanda Enayati ponders the theme of seeking serenity: the quest for well-being and life balance in stressful times. Earlier this week we put out a call over social media for your questions about stress and anxiety. We received a slew of insightful queries, covering a wide spectrum of life’s stressors. Due to the number of submissions, we had to combine some questions and divide our lightning round into two parts. Make sure to check back next week for part two, along with a synthesis of our experts’ advice. Our panel of experts includes: UC Davis professor Jay Belsky, a developmental psychologist and an internationally recognized expert on the role of nature and nurture in shaping children and families Dr. Judith Orloff, professor of psychiatry at UCLA and bestselling author of “ Emotional Freedom ” Dr. Rajita Sinha, professor of psychiatry, neurobiology and child study at Yale University and director of the Yale Stress Center I love my kids but… I adore my four little (but lively) children, but they stress me out. How can I better handle the stress of raising children, along with everything else that I have to do? This is a very common concern among parents. You need to find ways to relax and reduce your anxiety, whether it’s having a glass of wine (but not 3 or 4!), going to the gym, talking to a friend or meditating. Take time to remind yourself of the purpose of what you are doing, says Belsky. There is nothing more important than taking care of your children. There are also ways to make life with children less stressful. For example, institute a quiet time during some part of the day, when each family member goes someplace and does an activity by him or herself, like reading or listening to music. Learn how to set good boundaries, suggests Orloff. Set aside time alone to replenish because you cannot keep going non-stop. Mini-breaks can do wonders. Sinha recommends seeking family and social support, when possible. This also benefits children, who love to interact with – and hear – stories from other family members, like grandparents. Sinha also emphasizes the importance of taking breaks. Financial catastrophe I lost everything. First my job, then my savings and finally my home. What now? People have to deal with major adverse life events. This is uncontrollable stress, and it has the worst kind of impact in terms of a person’s ability to function. First, accept what has happened and then attempt to move beyond it. The most important thing is to optimize your own regulatory capacity, because it can affect your ability to problem-solve and come up with solutions effectively. Unrelenting stress can break that down. And though your circumstances may be challenging, it’s crucial to keep yourself in a positive and optimistic place. Seek help, get support and remember that there are many examples of people going through incredible catastrophes and coming out stronger. Belsky emphasizes the importance making external, rather than internal attributions about the cause of the adversities. Never forget that in many cases you are the victim, not the culprit, he says. “Don’t take ownership and responsibility for something you did not do. That’s not going to put money in your pocket but it will prevent you from beating up on yourself.” Be super-present and do not catastrophize the future, recommends Orloff. Focus on what you have. You must come at this issue from a very calm and centered place. People tend to work themselves up with worry. They can’t eat or sleep and then the situation deteriorates even further. Consider what you can do in the present moment. Nature or nurture? How much of stress and anxiety is nature versus nurture? You can’t attribute a set percentage of stress to genetics versus nurture, says Sinha. Nature gives us a certain predisposition, a basic structure for stress response. Some people are more reactive and some are less so. Nurture overlays that genetic structure and can support either the suppression or expression of those genes. Belsky also observes that some people tend to have a lower threshold for stress. A bit of noise can discombobulate one person, whereas another can tolerate cacophonous sounds. For some, nature is more important and for others nurture is. But, he cautions, we can’t truly ever know whether someone’s high anxiety levels are due to nature or nurture; it could be low tolerance or it could be because the person never learned to cope. While some of us may have been born more stressed-out and anxious than others, according to Orloff we create a lot of our own stress with the stories we tell about it. Many of Orloff’s patients create inordinate amounts of anxiety because of their unrelentingly negative thought patterns. She suggests taking control of your mind to create a more positive reality. “Be grateful for your breath, your life and what you have. If you choose your thoughts, you won’t get sucked into the vortex of negativity.” You versus food Food is freaking me out. I have no idea what we’re supposed to be eating anymore. It’s as if everything is bad for you and will kill you. Don’t be obsessive, says Orloff. There are people out there who won’t allow themselves a treat, but then the deprivation leads to binge eating. The bottom line is that you have to have a balanced attitude about food. Sure, it can be complicated, observes Belsky. But it can also be simple. The less junk food, the better. The more fruits, vegetables, cereals and whole grains, the better. And you certainly don’t have to aspire to eat a perfect diet all the time. Sinha recommends seeking the help of a nutritionist or certified dietician; both are often covered through health insurance plan as a health and wellness visit. These experts can help you track your present diet and make suggestions for healthier alternatives. They can also help develop sensible and sustainable meal plans. Family and other black holes My mother is the black hole of joy, but she’s my mother. How do I deal with her negativity? You have made a good start by having an understanding of who your mother is and how she makes you feel, says Belsky. You have to give yourself credit for understanding the situation because that will help guide how you proceed. Orloff addresses “emotional vampires” in her book, “ Emotional Freedom .” These are people who will suck you dry and, unfortunately, some mothers can be emotional vampires. Orloff warns against engaging negative people. “Don’t give emotional vampires any energy because they will keep going.” When they get negative or begin criticizing, set limits (by leaving, for example) or change the subject. People go wrong when they start engaging or believing the vitriol. We cannot control others’ behavior and outlook, observes Sinha. People frustrate us because we want them to be different. There are two key points here. The first is that you must accept people for who they are – good and bad. Their lives, genes and stressors have helped to shape them. Perhaps understanding where someone came from may help explain who he or she is now. But there is no light switch to make a person change; only a process of accepting him or her. The second point is that you do not have to change who you are. You have the right to have positive interactions and good energy in your life. Sometimes to make that happen, you need to get away from someone – and that’s okay too! But either way, the first step is acceptance. Next week we'll look at caretaker blues, internalizing stress, single parenting, the evolution of stress and information overload. Follow @amandaenayati on Twitter or on Facebook . Filed under: Stress Tagged: Amanda Enayati — Special to CNN

Countless Americans are suffering from thousands of diseases for which there are no treatments.  In an effort to develop new therapies for them, the National Institutes of Health launched a new program Thursday. The program is designed to match their researchers with experimental compounds currently not in further development from drug companies. "Americans are eagerly awaiting the next generation of cure and treatments to help them live linger and healthier lives. To accelerate our nation's therapeutic development process, it is essential that we forge strong, innovative and strategic partnerships across government, academia and industry," said Health and Human Services Secretary Kathleen Sebelius. The NIH's new National Center for Advancing Translational Sciences (NCATS) is partnering with pharmaceutical giants Pfizer, AstraZeneca and Eli Lilly and Company in a collaboration that will give researchers access to two dozen compounds or molecules to test their effectiveness against a host of diseases. NCATS will provide $20 million a year for the next three years starting in 2013. The compounds have already cleared a number of hurdles in the development process including safety testing in humans. NIH Director Francis Collins says he is happy to serve as a matchmaker. While researchers have identified the cause of more than 4,500 diseases, Collins says effective treatments are only available for about 250 of them. He hopes that compounds that were not effective against the disease they were originally developed for prove to be useful for other conditions. The HIV prevention drug AZT is an example of a drug that was a failure against it's first opponent – cancer. According to Collins, it currently takes on average $2 billion over a 14-year period to move a drug discovery from the lab to treatment. This new program would save researchers time and money because they wouldn't be starting from scratch. "Clearly, we need to speed the pace at which we are turning discoveries into better health outcomes," Collins said. "NIH looks forward to working with our partners in industry and academia to tackle an urgent need that is beyond the scope of any one organization or sector." According to the NIH, under the new agreement, drug companies will retain ownership of their compounds, and their research partners retain intellectual property rights and the rights to publish the research. At the time the contract is negotiated, the drug company and the investigator determine how the profits will be divided. Pfizer was the first drug company to sign on. "We have these wonderful molecules that have all the properties to be clinical research tools," Rod MacKenzie, group senior vice president, head of Pfizer PharmaTherapeutics Research and Development said. "The great hope that we have is having invested in these molecules already we may be able to connect with the great ideas and take these drugs all the way to market." Collins calls the program a "win, win, win" – for investors, pharmaceutical companies and for patients. "I'm hoping out of this comes real advances for people who are waiting for us to come up with answers." Filed under: Health and tech Tagged: Saundra Young – CNN Medical Senior Producer