Category Archives: Lose Weight
by Eric Hunter
(NaturalNews) Obese and lean individuals have different gut flora composition. The gut microbiota of mice and humans are similar, with Firmicutes and Bacteroidetes dominating. At this point it’s not clear exactly which species are important in weight management. Some studies show reduced numbers of Bacteroidetes in obese subjects, while others point to lower levels of beneficial bacteria like Lactobacillus.
Even though diet will affect gut flora composition, most studies conclude that gut flora on it’s own has an effect on weight. Alteration of the gut microbiota can be an important part of a weight loss program.
Several mechanisms have been proposed as to how gut flora regulates weight. Inflammation, energy from polysaccharides, insulin sensitivity and energy expenditure and storage are all affected by gut flora.
What you eat affects the gut flora composition, but it can also be hypothesized that it can happen the other way around; that gut flora partly determines what you eat. People with gut dysbiosis and especially yeast overgrowth often feel sugar cravings. Gut flora can probably influence food cravings and thereby play a part in determining dietary choices.
Obesity is hereditary, and the importance of gut flora shouldn’t be underestimated. Flora is passed on from mother to child during birth, breastfeeding and early years. The child also comes in contact with microorganisms from other family members. “Obese gut flora” is passed on to the child.
Children born via caesarean have double the risk of becoming overweight, according to research by Harvard scientists. The obesity increase has been linked to a lack of exposure to good bacteria which may be found in the vaginal wall.
Differences in intestinal microflora during the first year of life have been associated with higher risk of obesity later in life. Especially low levels of Bifidobacteria make children more susceptible to weight gain.
Obese individuals usually have a dysfunctional gut flora with higher numbers of LPS-containing microbiota and methane-producing bacteria. LPS, Lipopolysaccharide, is linked to obesity, leaky gut and low-level chronic inflammation.
Colonization of germ-free mice with gut flora from either obese or lean mice, leads to significantly greater increase in total body fat in those colonized with “obese microbiota.” Animal studies further show that probiotic supplements with Lactobacillus and Bifidobacterium species help maintain a healthy bodyweight and promote weight-loss. Cattle treated with antibiotics store a lot of fat, and this is one of the reasons why these drugs are used so frequently in feedlots.
How to incorporate this info into your weight loss program
A healthy diet with reduced consumption of sugar, processed carbohydrates, most vegetable oils, anti-nutrients, etc. will on it’s own promote weight loss and a healthier gut flora.
Additional gut flora modifications can also be an important part of a weight-loss plan. Simply eating yoghurt will not make any substantial difference in most people. Minimally washed organic plants and plant products, fermented foods and probiotic supplements are all good sources of beneficial bacteria. Prebiotics, soluble fiber that feed good bacteria, can be found in leeks, onions, apples etc.
Sources for this article include
Obesity alters gut microbial ecology.Ley, et al. Proc Natl Acad Sci USA. 2005 Aug 2; 102(31):11070-11075.
Vael C, Verhulst SL, Nelen V, et al. Intestinal microflora and body mass index during the first three years of life: an observational study.
Gut Pathog. 2011 May 23;3(1):8.
Kalliomaki M., Collado M.C, Salminen S., et al. Early differences in fecal microbiota composition in children may predict overweight
Am J Clin Nutr March 2008 vol. 87 no. 3 534-538
Kondo S, Xiao JZ, Satoh T, et al. Antiobesity effects of Bifidobacterium breve strain B-3 supplementation in a mouse model with high-fat diet-induced obesity.
Biosci Biotechnol Biochem. 2010;74(8):1656-61. Epub 2010 Aug 7.
Takemura N, Okubo T, Sonoyama K. Lactobacillus plantarum strain No. 14 reduces adipocyte size in mice fed high-fat diet.
Exp Biol Med (Maywood). 2010 Jul;235(7):849-56.
Chen JJ, Wang R, Li XF, et al. Bifidobacterium longum supplementation improved high-fat-fed-induced metabolic syndrome and promoted intestinal Reg I gene expression.
Exp Biol Med (Maywood). 2011 Jul 1;236(7):823-31. Epub 2011 Jun 17.
Karlsson CL, Molin G, Fak F, et al. Effects on weight gain and gut microbiota in rats given bacterial supplements and a high-energy-dense diet from fetal life through to 6 months of age.
Br J Nutr. 2011 Sep;106(6):887-95. Epub 2011 Mar 30.
Human originated bacteria, Lactobacillus rhamonosus PL60, produce conjugated linoleic acid and show anti-obesity effects in diet-induced obese mice.Lee, et al. Biochem Biophys Acta. 2006 Jul;1761(7):736-744
Metabolic endotoxemia initiates obesity and insulin resistance.Cani, et al. Diabetes. 2007 Jul;56(7):1761-1772
Anyone who is overweight will testify that losing weight is not as easy as it seems. The people that are lean, or have gone from fat to skinny will say it’s just a matter of motivation and elbow grease. Although it is not as simple as that. Our environments have waged war on us. Their weapons are sedentary lives and trans fats of mass destruction. All is not lost though, here are some quick simple tips to get ahead!
1. Substitute Water. Our bodies are about 65-70% water. It follows that water would be not only essential, but the best possibly choice of liquids to ingest. In fact, our bodies will sometimes simulate a hunger response, when in reality the body is craving hydration. When hungry, drink a glass or two of water to check if it suppresses your hunger.
2. Chew Your Food. Chewing our food very slowly and deliberately has several benefits that are often overlooked. It gives us the ability to relax, and enjoy our meal. Slow chewing is the first, and highly important, step in a complex system of digestion. Besides, if we eat slowly, we might feel full before finishing the whole meal, and can leave the rest for the next meal.
3. Exercise daily. How silly of me to include something as obvious as exercise. I did a 30 day trial with waking up, and walking for 30 minutes first thing in the morning. My journal records that I was feeling amazing during the period of time that I was following this habit.
4. Publicize your intentions. Start a blog, join a forum, and have other people keep you accountable to help. Tell other people your plan, it would help you get the motivation to go with it!
5. Create a food schedule. Plan your day so that youâ€™re eating at approximately the same time each day. This scheduling will incorporate itself into your circadian rhythm, and aid in digestion.
6. Do not over eat. Know your limit and stop eating when you are full. I have often been a victim of wanting to finish a meal so that it doesn’t go to waste. This has left me with many a stomach ache. Next time, doggy bag it for later, and don’t hurt yourself!
7. Choose your snacks wisely. Put down the Lays and cheese puffs. Pick up the apple and baby carrots. Make the right decision, I know you can do it.
8. Lifestyle. Remember, it’s not about special diets, or special exercise programs. The real secret is in turning your health into a lifestyle, and focusing on this healthy lifestyle with every choice you make
By: Allison Winn Scotch
When your boss says, “We’re not here to assign blame,” duck. When we say you’re not entirely to blame for your paunch, you’re not off the hook. Nobody is the innocent victim of a drive-thru feeding. But there are sneaky factors—your friends, your family, your mindset—that can sabotage the best weight-loss plan. Your strategy: Identify the saboteurs, then adjust.
We do not suggest blaming her for your belly. This would be (a) wrong and (b) a reasonable defense at her trial. But know this: Researchers at the University of Minnesota found that men and women usually gain 6 to 8 pounds in the first 2 years of marriage. “Once you’re married, that need to impress is gone,” says Edward Abramson, Ph.D., author of Marriage Made Me Fat. “You may go to the gym less often, go out for meals or to parties more frequently, and develop new rituals, such as sitting on the couch with your wife and snacking.”
Fix your head: Regain that need to impress. Imagine what that girl at the gym thinks of your gut—or what she’d think if you had abs. (Just don’t hit on her.) As for that bowl of popcorn with your wife, Abramson says, ask yourself, Why am I eating? Boredom? Habit? Better yet, ask her to stop bringing those binge foods into the house.
Fix your routine: Establish healthful rituals. Instead of Access Hollywood after dinner, take regular walks, or play H-O-R-S-E in the driveway. (P-I-G might work better.) Exercise suppresses appetite. Cool down with Italian ice (120 calories per cup) instead of ice cream (290 calories per cup).
Dads-to-be gain almost 5 pounds from the end of their partner’s pregnancy to the baby’s first birthday, Australian researchers report. It’s especially common in young, stressed-out fathers, says Lawrence Schwartz, author of Fat Daddy/Fit Daddy. And the cycle repeats with each kid.
Fix your head: Be a heroic provider, not a sympathetic eater. Prepare as if fatherhood were a sport—because it will be.
Fix your routine: Read her pregnancy books—they’re full of excellent nutritional advice. As for her binge snacking and ice-cream jags, adopt a simple policy, says Schwartz: “She can have it, but you shouldn’t.” Maintain your exercise routine, especially weight lifting. “It’s only going to be that much harder to get back into an exercise routine once the baby’s here,” says Schwartz.
The presence of children in a household sharply increases the likelihood of tempting junk food in the cupboard. Some of it ends up in adult mouths. Same goes for stray nuggets and fries left over by finicky kids. “I call this ‘trolling,’ ” Schwartz says. “If you’re prone to troll, the easiest thing to do is to avoid the Happy Meal altogether.”
Fix your head: Grow up. Think: The sugary snack that a child will burn off with an hour of fidgeting will haunt you as a fat deposit. Read the nutrition label on any snack before unwrapping it. Realize the importance of setting a good food-and-exercise example.
Fix your routine: Make junk food a once-a-week thing. Designate Friday as Twinkie day. And instead of standing on the sidelines to watch your son’s game, volunteer to coach, ump, or ref. Make fitness a family thing.
Not getting enough deep, non-REM sleep inhibits production of growth hormone, which might lead to premature middle-age symptoms—abdominal obesity, reduced muscle mass and strength, and diminished exercise capacity. You become Homer.
Fix your head: “Mentally disengage yourself before you hit the sack,” says Jim Karas, author of The Business Plan for Your Body. Don’t plot a staffing reorg before bed.
Fix your routine: Exercise in the morning or afternoon, says Eric Nofzinger, M.D., director of sleep neuroimaging research at the Western Psychiatric Institute. Evening workouts may leave you too stimulated to sleep. Establish a ritual that signals your body that the day is over 30 minutes before bedtime—turn off the computer, read, stretch, or set the TV volume low, says Karas.
Workers gain 7 pounds on average when they switch from a day to a night shift, according to the New York Obesity Research Center. Men working the graveyard shift tend to eat a big evening meal and go to work, says Jim Waterhouse, Ph.D., author of Keeping in Time with Your Body Clock. “Then they come home to another ‘supper’ in the morning.”
Fix your head: Adjust your concept of mealtime, says Waterhouse.
Fix your routine: Eat your biggest meal when you get home from your shift, Waterhouse says, then relax or exercise in the morning. Get 8 hours of sleep in the afternoon, then wake up and have breakfast. Kicking off your workday (even if it starts in the evening) with a light meal that’s high in protein or fiber is crucial for weight loss.
Stress will spike levels of the hormone cortisol, which tells your body to store fat. “Unfortunately, some people appease their anxiety by reaching for fatty foods,” says Elissa Epel, Ph.D., an assistant professor of psychiatry at the University of California at San Francisco. Eating boosts insulin levels; combining that with cortisol leads to greater fat deposits. More stress, bigger belly.
Fix your head: First, identify the type of stress you’re under, Karas says. “Is it temporary, like a bar exam, or more permanent, like your job?” Short-term stress will pass. Long-term stress may require a permanent solution, like a new job.
Fix your routine: Make healthy eating effortless, Karas says. Buy snacks that won’t send insulin levels soaring: high-fiber energy bars or single-serving bags of almonds or cashews. Fifteen minutes of explosive activity—hitting a speed bag or jumping rope—can alleviate anxieties after work. “It’s about getting the tension out,” Karas says.
Buddies can make or break a diet or workout plan, whether it’s unconscious scarfing of nachos during the game or the lure of pumping beers instead of iron. Worse, some guys will deliberately try to sabotage your diet, just for sport. Want a cookie?
Fix your head: Admit you need support. “Let people know how to help you, and many will,” says Beth Kitchin, an assistant professor of nutritional sciences at the University of Alabama at Birmingham.
Fix your routine: Eat a protein bar before meeting friends, so you?ll feel fuller. Drink a glass of water for every glass of beer. A time-tested strategy: Recruit a friend to diet or work out with you. Having someone to answer to is the best enforcement plan.
Always Eat a Man’s Breakfast
No more Lucky Charms—you want some protein and fat. Scrambled eggs and a few sausage links will keep you fuller longer than an airy doughnut will.
We’re talking three good snacks and three healthful meals. But what do you serve during the bowl game if you can’t have chips and dip? Mixed nuts—especially almonds—will satisfy your craving for something crunchy while helping to build muscle.
Just Say No to Starches
Foods like pasta, white bread, and potatoes make you fat. If you must have pasta, make yours whole-wheat. Same goes for bread, and swap white potatoes for sweet potatoes. Just don’t eat too much!
Yes, you have to hit the gym, and no, lifting beer cans during happy hour doesn’t count. The muscles you build will not only improve your performance, they’ll stoke your metabolism so you burn calories long after your workout is over.
Think Before You Eat
Don’t just stuff your face with the stale cookies left over from the holidays, eat what tastes good and what’s good for you. Take your time eating; you’ll stay fuller longer.
But Have Fun Once in a While—or Once a Week
Stifle those cravings for too long, and you’ll be miserable and might fall off your new plan forever. Just splurge reasonably—two slices of pizza, not the whole thing.
It’s the easiest way to drop weight fast. The cravings are hard at first, but it gets easier—especially when you see the results.
It’s easier to alternate between hard and easy running instead of going for a long run—especially if you don’t like running. Plus, you’ll be done faster and burn more fat.
Never, Ever Drink Sweetened Soda
But go ahead, have a glass of wine now and then. Low-carb beer is fine, too, in moderation.
Don’t Fear Fat
It makes you feel full, helps control your appetite, and your body needs it.
By: David Schipper
Recently, Cornell University researchers asked a group of people a simple question: “How do you know when you’re through eating dinner?”
The answer might seem obvious. After all, doesn’t everyone push the plate away when they feel full? Well, no. The leanest people do, according to the scientists, but people who are overweight rely more on what are known as “external cues.” For example, guys packing a few extra pounds tend to stop eating when . . .
1. Their plates are clean.
2. Everyone else in their group is finished.
3. The TV show they’re watching is over.
Unfortunately, these cues have nothing to do with how they feel physically. “People’s brains are often out of touch with their bodies,” says C. Peter Herman, Ph.D., a University of Toronto expert on appetite control. “And when eating becomes mindless, overeating becomes routine.”
The key player in all of this appears to be a region of your brain called the left posterior amygdala, or LPA. This area monitors the volume of food in your stomach during a meal. Fill your gut to a comfortable level, and the LPA tells your brain to drop the fork. Trouble is, it delivers that information at dial-up speed in a DSL world. “Many men consume calories faster than their bodies can say, ‘Stop!'” explains Herman. “So they look to external cues to guide their consumption.”
The bottom line is this: To shrink your gut, you need to start listening to it. We’ve scoured the science and tapped the top experts to help you learn how to do just that. Use these seven simple strategies, and you’ll fill up without filling out.
Sit Down to Snack
Turns out, the trappings of a formal meal make you think you’re eating more than you actually are—and that may boost satiety levels. A 2006 Canadian study found that when people ate lunch while sitting at a set table, they consumed a third less at a later snack than those who ate their midday meals while standing at a counter.
Think of it as the Zen of eating: “If you treat every dining experience with greater respect, you’ll be less likely to use your fork as a shovel,” says sports nutritionist and behavioral psychotherapist Lisa Dorfman, M.S., R.D. “And that includes snacks as well as your three squares.”
Turn Off the Tube
University of Massachusetts researchers found that people who watched TV during a meal consumed 288 more calories on average than those who didn’t. The reason: What you’re seeing on television distracts you, which keeps your brain from recognizing that you’re full.
Slow Down and Savor
“Pay close attention to those first three bites, which people usually wolf down due to excitement,” says Jeffrey Greeson, Ph.D., a health psychologist at Duke Integrative Medicine. In fact, mimic a food critic: “Examine the food’s texture, savor the flavors in your mouth, and then pay attention and feel the swallow,” he says. “Psychologically, this form of meditative eating boosts satiety and promotes a sense of satisfaction for the entire meal.”
While you’re at it, try spicing up relatively bland fare, such as scrambled eggs, with hot sauce or smoked paprika. “Hot, flavorful foods help trigger your brain to realize you’re eating,” says Dorfman.
Take a Bite, Take a Breath
University of Rhode Island researchers discovered that consciously slowing down between bites decreases a person’s calorie intake by 10 percent. “Breathing helps you gauge how hungry you are, since it directs your mind toward your body,” says Greeson. “It’s also quite practical, since you can do it throughout a meal and not draw attention to yourself in a social situation.”
Don’t Share Your Food
Researchers at the State University of New York at Buffalo observed that men who ate with a group of buddies downed 60 percent more calories than when they ate with a spouse or girlfriend. That’s because people often match their intake of food to that of their dining partners.
Of course, you shouldn’t have to sit home on guys’ night out. Choose one reasonable entrée for yourself, and skip the communal foods—bread, nachos, wings, and pizza, for example—which encourage you to take your eating cues from pals.
Keep a Food Journal
It’s an effective way to remind yourself how much you’re eating over the course of a day. But it doesn’t need to be complicated: University of Pittsburgh scientists found that dieters who simply wrote down the size of each meal (S, M, L, XL) were just as successful at losing weight as those who tracked specific foods and calorie counts.
One useful addition: Detail the motivation behind your eating habits. “Were you really hungry or just blowing off steam before bedtime? Recognizing that you weren’t feeling true hunger reinforces the idea of listening to your body,” says Dorfman.
Don’t Trust the “Healthy” Menu
You’re likely to underestimate your meal’s calorie count by about 35 percent, according to a new study published in the Journal of Consumer Research. The best approach is to check the restaurant’s nutrition guide before you order. A University of Mississippi study found that people consumed 54 percent fewer calories when they used this simple strategy.
As I write this, tomorrow is Tuesday, which is a cardio day. I’ll spend five minutes warming up on the VersaClimber, a towering machine that requires you to move your arms and legs simultaneously. Then I’ll do 30 minutes on a stair mill. On Wednesday a personal trainer will work me like a farm animal for an hour, sometimes to the point that I am dizzy — an abuse for which I pay as much as I spend on groceries in a week. Thursday is “body wedge” class, which involves another exercise contraption, this one a large foam wedge from which I will push myself up in various hateful ways for an hour. Friday will bring a 5.5-mile run, the extra half-mile my grueling expiation of any gastronomical indulgences during the week.
I have exercised like this — obsessively, a bit grimly — for years, but recently I began to wonder: Why am I doing this? Except for a two-year period at the end of an unhappy relationship — a period when I self-medicated with lots of Italian desserts — I have never been overweight. One of the most widely accepted, commonly repeated assumptions in our culture is that if you exercise, you will lose weight. But I exercise all the time, and since I ended that relationship and cut most of those desserts, my weight has returned to the same 163 lb. it has been most of my adult life. I still have gut fat that hangs over my belt when I sit. Why isn’t all the exercise wiping it out? (Read “The Year in Medicine 2008: From A to Z.”)
It’s a question many of us could ask. More than 45 million Americans now belong to a health club, up from 23 million in 1993. We spend some $19 billion a year on gym memberships. Of course, some people join and never go. Still, as one major study — the Minnesota Heart Survey — found, more of us at least say we exercise regularly. The survey ran from 1980, when only 47% of respondents said they engaged in regular exercise, to 2000, when the figure had grown to 57%.
And yet obesity figures have risen dramatically in the same period: a third of Americans are obese, and another third count as overweight by the Federal Government’s definition. Yes, it’s entirely possible that those of us who regularly go to the gym would weigh even more if we exercised less. But like many other people, I get hungry after I exercise, so I often eat more on the days I work out than on the days I don’t. Could exercise actually be keeping me from losing weight? (Watch TIME’s video “How to Lose Hundreds of Pounds.”)
The conventional wisdom that exercise is essential for shedding pounds is actually fairly new. As recently as the 1960s, doctors routinely advised against rigorous exercise, particularly for older adults who could injure themselves. Today doctors encourage even their oldest patients to exercise, which is sound advice for many reasons: People who regularly exercise are at significantly lower risk for all manner of diseases — those of the heart in particular. They less often develop cancer, diabetes and many other illnesses. But the past few years of obesity research show that the role of exercise in weight loss has been wildly overstated. (Read “Losing Weight: Can Exercise Trump Genes?”)
“In general, for weight loss, exercise is pretty useless,” says Eric Ravussin, chair in diabetes and metabolism at Louisiana State University and a prominent exercise researcher. Many recent studies have found that exercise isn’t as important in helping people lose weight as you hear so regularly in gym advertisements or on shows like The Biggest Loser — or, for that matter, from magazines like this one.
The basic problem is that while it’s true that exercise burns calories and that you must burn calories to lose weight, exercise has another effect: it can stimulate hunger. That causes us to eat more, which in turn can negate the weight-loss benefits we just accrued. Exercise, in other words, isn’t necessarily helping us lose weight. It may even be making it harder.
The Compensation Problem
Earlier this year, the peer-reviewed journal PLoS ONE — PLoS is the nonprofit Public Library of Science — published a remarkable study supervised by a colleague of Ravussin’s, Dr. Timothy Church, who holds the rather grand title of chair in health wisdom at LSU. Church’s team randomly assigned into four groups 464 overweight women who didn’t regularly exercise. Women in three of the groups were asked to work out with a personal trainer for 72 min., 136 min., and 194 min. per week, respectively, for six months. Women in the fourth cluster, the control group, were told to maintain their usual physical-activity routines. All the women were asked not to change their dietary habits and to fill out monthly medical-symptom questionnaires.
The findings were surprising. On average, the women in all the groups, even the control group, lost weight, but the women who exercised — sweating it out with a trainer several days a week for six months — did not lose significantly more weight than the control subjects did. (The control-group women may have lost weight because they were filling out those regular health forms, which may have prompted them to consume fewer doughnuts.) Some of the women in each of the four groups actually gained weight, some more than 10 lb. each.
What’s going on here? Church calls it compensation, but you and I might know it as the lip-licking anticipation of perfectly salted, golden-brown French fries after a hard trip to the gym. Whether because exercise made them hungry or because they wanted to reward themselves (or both), most of the women who exercised ate more than they did before they started the experiment. Or they compensated in another way, by moving around a lot less than usual after they got home. (Read “Run For Your Lives.”)
The findings are important because the government and various medical organizations routinely prescribe more and more exercise for those who want to lose weight. In 2007 the American College of Sports Medicine and the American Heart Association issued new guidelines stating that “to lose weight … 60 to 90 minutes of physical activity may be necessary.” That’s 60 to 90 minutes on most days of the week, a level that not only is unrealistic for those of us trying to keep or find a job but also could easily produce, on the basis of Church’s data, ravenous compensatory eating.
It’s true that after six months of working out, most of the exercisers in Church’s study were able to trim their waistlines slightly — by about an inch. Even so, they lost no more overall body fat than the control group did. Why not?
Church, who is 41 and has lived in Baton Rouge for nearly three years, has a theory. “I see this anecdotally amongst, like, my wife’s friends,” he says. “They’re like, ‘Ah, I’m running an hour a day, and I’m not losing any weight.'” He asks them, “What are you doing after you run?” It turns out one group of friends was stopping at Starbucks for muffins afterward. Says Church: “I don’t think most people would appreciate that, wow, you only burned 200 or 300 calories, which you’re going to neutralize with just half that muffin.” (Read “Too Fat? Read Your E-mail.”)
You might think half a muffin over an entire day wouldn’t matter much, particularly if you exercise regularly. After all, doesn’t exercise turn fat to muscle, and doesn’t muscle process excess calories more efficiently than fat does?
Yes, although the muscle-fat relationship is often misunderstood. According to calculations published in the journal Obesity Research by a Columbia University team in 2001, a pound of muscle burns approximately six calories a day in a resting body, compared with the two calories that a pound of fat burns. Which means that after you work out hard enough to convert, say, 10 lb. of fat to muscle — a major achievement — you would be able to eat only an extra 40 calories per day, about the amount in a teaspoon of butter, before beginning to gain weight. Good luck with that.
Fundamentally, humans are not a species that evolved to dispose of many extra calories beyond what we need to live. Rats, among other species, have a far greater capacity to cope with excess calories than we do because they have more of a dark-colored tissue called brown fat. Brown fat helps produce a protein that switches off little cellular units called mitochondria, which are the cells’ power plants: they help turn nutrients into energy. When they’re switched off, animals don’t get an energy boost. Instead, the animals literally get warmer. And as their temperature rises, calories burn effortlessly. (See TIME’s health and medicine covers.)
Because rodents have a lot of brown fat, it’s very difficult to make them obese, even when you force-feed them in labs. But humans — we’re pathetic. We have so little brown fat that researchers didn’t even report its existence in adults until earlier this year. That’s one reason humans can gain weight with just an extra half-muffin a day: we almost instantly store most of the calories we don’t need in our regular (“white”) fat cells.
All this helps explain why our herculean exercise over the past 30 years — all the personal trainers, StairMasters and VersaClimbers; all the Pilates classes and yoga retreats and fat camps — hasn’t made us thinner. After we exercise, we often crave sugary calories like those in muffins or in “sports” drinks like Gatorade. A standard 20-oz. bottle of Gatorade contains 130 calories. If you’re hot and thirsty after a 20-minute run in summer heat, it’s easy to guzzle that bottle in 20 seconds, in which case the caloric expenditure and the caloric intake are probably a wash. From a weight-loss perspective, you would have been better off sitting on the sofa knitting.
Self-Control Is like a Muscle
Many people assume that weight is mostly a matter of willpower — that we can learn both to exercise and to avoid muffins and Gatorade. A few of us can, but evolution did not build us to do this for very long. In 2000 the journal Psychological Bulletin published a paper by psychologists Mark Muraven and Roy Baumeister in which they observed that self-control is like a muscle: it weakens each day after you use it. If you force yourself to jog for an hour, your self-regulatory capacity is proportionately enfeebled. Rather than lunching on a salad, you’ll be more likely to opt for pizza.
Some of us can will ourselves to overcome our basic psychology, but most of us won’t be very successful. “The most powerful determinant of your dietary intake is your energy expenditure,” says Steven Gortmaker, who heads Harvard’s Prevention Research Center on Nutrition and Physical Activity. “If you’re more physically active, you’re going to get hungry and eat more.” Gortmaker, who has studied childhood obesity, is even suspicious of the playgrounds at fast-food restaurants. “Why would they build those?” he asks. “I know it sounds kind of like conspiracy theory, but you have to think, if a kid plays five minutes and burns 50 calories, he might then go inside and consume 500 calories or even 1,000.” (Read “Why Kids’ Exercise Matters Less Than We Think.”)
Last year the International Journal of Obesity published a paper by Gortmaker and Kendrin Sonneville of Children’s Hospital Boston noting that “there is a widespread assumption that increasing activity will result in a net reduction in any energy gap” — energy gap being the term scientists use for the difference between the number of calories you use and the number you consume. But Gortmaker and Sonneville found in their 18-month study of 538 students that when kids start to exercise, they end up eating more — not just a little more, but an average of 100 calories more than they had just burned.
If evolution didn’t program us to lose weight through exercise, what did it program us to do? Doesn’t exercise do anything?
Sure. It does plenty. In addition to enhancing heart health and helping prevent disease, exercise improves your mental health and cognitive ability. A study published in June in the journal Neurology found that older people who exercise at least once a week are 30% more likely to maintain cognitive function than those who exercise less. Another study, released by the University of Alberta a few weeks ago, found that people with chronic back pain who exercise four days a week have 36% less disability than those who exercise only two or three days a week.
But there’s some confusion about whether it is exercise — sweaty, exhausting, hunger-producing bursts of activity done exclusively to benefit our health — that leads to all these benefits or something far simpler: regularly moving during our waking hours. We all need to move more — the Centers for Disease Control and Prevention says our leisure-time physical activity (including things like golfing, gardening and walking) has decreased since the late 1980s, right around the time the gym boom really exploded. But do we need to stress our bodies at the gym?
Look at kids. In May a team of researchers at Peninsula Medical School in the U.K. traveled to Amsterdam to present some surprising findings to the European Congress on Obesity. The Peninsula scientists had studied 206 kids, ages 7 to 11, at three schools in and around Plymouth, a city of 250,000 on the southern coast of England. Kids at the first school, an expensive private academy, got an average of 9.2 hours per week of scheduled, usually rigorous physical education. Kids at the two other schools — one in a village near Plymouth and the other an urban school — got just 2.4 hours and 1.7 hours of PE per week, respectively.
To understand just how much physical activity the kids were getting, the Peninsula team had them wear ActiGraphs, light but sophisticated devices that measure not only the amount of physical movement the body engages in but also its intensity. During four one-week periods over consecutive school terms, the kids wore the ActiGraphs nearly every waking moment.
And no matter how much PE they got during school hours, when you look at the whole day, the kids from the three schools moved the same amount, at about the same intensity. The kids at the fancy private school underwent significantly more physical activity before 3 p.m., but overall they didn’t move more. “Once they get home, if they are very active in school, they are probably staying still a bit more because they’ve already expended so much energy,” says Alissa Frémeaux, a biostatistician who helped conduct the study. “The others are more likely to grab a bike and run around after school.”
Another British study, this one from the University of Exeter, found that kids who regularly move in short bursts — running to catch a ball, racing up and down stairs to collect toys — are just as healthy as kids who participate in sports that require vigorous, sustained exercise.
Could pushing people to exercise more actually be contributing to our obesity problem? In some respects, yes. Because exercise depletes not just the body’s muscles but the brain’s self-control “muscle” as well, many of us will feel greater entitlement to eat a bag of chips during that lazy time after we get back from the gym. This explains why exercise could make you heavier — or at least why even my wretched four hours of exercise a week aren’t eliminating all my fat. It’s likely that I am more sedentary during my nonexercise hours than I would be if I didn’t exercise with such Puritan fury. If I exercised less, I might feel like walking more instead of hopping into a cab; I might have enough energy to shop for food, cook and then clean instead of ordering a satisfyingly greasy burrito.
Closing the Energy Gap
The problem ultimately is about not exercise itself but the way we’ve come to define it. Many obesity researchers now believe that very frequent, low-level physical activity — the kind humans did for tens of thousands of years before the leaf blower was invented — may actually work better for us than the occasional bouts of exercise you get as a gym rat. “You cannot sit still all day long and then have 30 minutes of exercise without producing stress on the muscles,” says Hans-Rudolf Berthoud, a neurobiologist at LSU’s Pennington Biomedical Research Center who has studied nutrition for 20 years. “The muscles will ache, and you may not want to move after. But to burn calories, the muscle movements don’t have to be extreme. It would be better to distribute the movements throughout the day.”
For his part, Berthoud rises at 5 a.m. to walk around his neighborhood several times. He also takes the stairs when possible. “Even if people can get out of their offices, out from in front of their computers, they go someplace like the mall and then take the elevator,” he says. “This is the real problem, not that we don’t go to the gym enough.” (Read “Is There a Laziness Gene?”)
I was skeptical when Berthoud said this. Don’t you need to raise your heart rate and sweat in order to strengthen your cardiovascular system? Don’t you need to push your muscles to the max in order to build them?
Actually, it’s not clear that vigorous exercise like running carries more benefits than a moderately strenuous activity like walking while carrying groceries. You regularly hear about the benefits of exercise in news stories, but if you read the academic papers on which these stories are based, you frequently see that the research subjects who were studied didn’t clobber themselves on the elliptical machine. A routine example: in June the Association for Psychological Science issued a news release saying that “physical exercise … may indeed preserve or enhance various aspects of cognitive functioning.” But in fact, those who had better cognitive function merely walked more and climbed more stairs. They didn’t even walk faster; walking speed wasn’t correlated with cognitive ability.
There’s also growing evidence that when it comes to preventing certain diseases, losing weight may be more important than improving cardiovascular health. In June, Northwestern University researchers released the results of the longest observational study ever to investigate the relationship between aerobic fitness and the development of diabetes. The results? Being aerobically fit was far less important than having a normal body mass index in preventing the disease. And as we have seen, exercise often does little to help heavy people reach a normal weight. (Read “Physical Fitness — How Not to Get Sick.”)
So why does the belief persist that exercise leads to weight loss, given all the scientific evidence to the contrary? Interestingly, until the 1970s, few obesity researchers promoted exercise as critical for weight reduction. As recently as 1992, when a stout Bill Clinton became famous for his jogging and McDonald’s habits, the American Journal of Clinical Nutrition published an article that began, “Recently, the interest in the potential of adding exercise to the treatment of obesity has increased.” The article went on to note that incorporating exercise training into obesity treatment had led to “inconsistent” results. “The increased energy expenditure obtained by training may be compensated by a decrease in non-training physical activities,” the authors wrote.
Then how did the exercise-to-lose-weight mantra become so ingrained? Public-health officials have been reluctant to downplay exercise because those who are more physically active are, overall, healthier. Plus, it’s hard even for experts to renounce the notion that exercise is essential for weight loss. For years, psychologist Kelly Brownell ran a lab at Yale that treated obese patients with the standard, drilled-into-your-head combination of more exercise and less food. “What we found was that the treatment of obesity was very frustrating,” he says. Only about 5% of participants could keep the weight off, and although those 5% were more likely to exercise than those who got fat again, Brownell says if he were running the program today, “I would probably reorient toward food and away from exercise.” In 2005, Brownell co-founded Yale’s Rudd Center for Food Policy and Obesity, which focuses on food marketing and public policy — not on encouraging more exercise.
Some research has found that the obese already “exercise” more than most of the rest of us. In May, Dr. Arn Eliasson of the Walter Reed Army Medical Center reported the results of a small study that found that overweight people actually expend significantly more calories every day than people of normal weight — 3,064 vs. 2,080. He isn’t the first researcher to reach this conclusion. As science writer Gary Taubes noted in his 2007 book Good Calories, Bad Calories: Fats, Carbs, and the Controversial Science of Diet and Health, “The obese tend to expend more energy than lean people of comparable height, sex, and bone structure, which means their metabolism is typically burning off more calories rather than less.”
In short, it’s what you eat, not how hard you try to work it off, that matters more in losing weight. You should exercise to improve your health, but be warned: fiery spurts of vigorous exercise could lead to weight gain. I love how exercise makes me feel, but tomorrow I might skip the VersaClimber — and skip the blueberry bar that is my usual postexercise reward.