Tag Archives: weight loss

Eat slow, then fast. How and when you eat may be as important as what you eat for weight control.

What you eat is an essential part of achieving and maintaining good health. What you may not know is that when and how you eat can be just as important. This is especially true if your goal is to lose weight.

My Health & Fitness column in the Aiken Standard this week describes  two ways that changing the way you eat can help you lose weight and keep it off. Neither of these are necessarily new ideas, but implementing them together may help you eat less.

First, eating more slowly can help you limit the amount of food you eat. Perhaps your mother admonished you to “slow down” at meals when you were young. This was good advice, for both practical and physiological reasons. In addition to controlling how much food you consume, eating more slowly is a good way to enjoy meals, both the food and the company, more fully.

You mother may also have told you to “chew your food.” too. This was probably to remind you to eat more slowly.  Almost 100 years ago Horace Fletcher recommended a process that involved chewing each bite of food 100 times. “Fletcherizing,” as it was called, was a way to reduce how much people ate, among other more dubious health claims.

There is a physiological reason to slow down, too. Your appetite is regulated by a host of factors, including the act of eating and the presence of food in your stomach. As you eat, your stomach fills. This triggers the release of hormones that signal your brain to reduce your appetite. The result is that as your stomach fills, you feel less hungry.

Once you start eating, it takes time for your stomach to release these hormones. Eating quickly, like many of us do, allows you to take in lots of calories before your brain gets the message that you are full. This is one factor that leads to overeating. But if you slow down at meals, you start to feel full before you eat as much. Research shows that this can lead to lower calorie intake during the meal.

Second, the time between meals may affect your metabolism in ways that result in less fat accumulation. Again, the concept of fasting between meals isn’t new, but recent research helps explain why eating less frequently may help prevent obesity and related conditions, including diabetes.

While this research was done using rats, the physiological concept may well apply to humans. In these studies, rats were put on a diet that included an overnight fast ranging from 8–12 hours. The researchers found that the rats that experienced a longer fasting period between meals had better insulin levels and less fat storage.

The reason for this seems to do with the gut microbiome, the bacteria that live in the intestine and play an important role in regulating metabolism. A longer period without food changes the nature of these good bacteria, promoting these benefits.

I first heard about this on Science Friday, which provides an excellent summary of this research.

It is unclear whether this same effect occurs in humans. Even without this evidence, adopting a fasting period between dinner and breakfast, which should be about 12 hours, seems prudent. At the very least, it will keep you from snacking in the evening, which almost certainly involves unhealthy choices.

An additional finding of this research is that the benefits of the 12-hour fast seem to persist, even through a day or two of more frequent eating. This is relevant, since many people do well to modify their eating habits during the week, but tend toward less restrained eating on the weekends. The fact that the benefits of an overnight fast most days of the week are maintained despite a “wild weekend” is good news!

The combination of what, when, and how you eat can make an important difference in how much you eat, the key to losing weight and keeping it off. As you try to make healthier food choices, consider eating more slowly and making dinner the end of your eating day.

It’s about time.

My Health & Fitness column in the Aiken Standard this week is about time—why dedicating adequate time is essential for exercise and weight loss success and suggestions for how to spend your time to achieve health and fitness goals.


Improving your health through diet, exercise, and weight loss takes motivation and dedication. It also takes time. This includes time to learn about what you should (and shouldn’t) do as well as the time needed to modify these health habits. For many, the problem isn’t knowing what to do or how to get started, it is finding the time to stick with the program. In fact, the number one reason why people abandon their diet and exercise routine is lack of time.

Given that most people are busy—maybe too busy—with work, family, and other responsibilities, finding time to focus on health isn’t easy. But it is important, so the first step should be dedicating your time wisely to meet your goals. This involves time for planning, taking action, and monitoring your progress. In short, you should treat your diet or exercise program like a project, rather than an “extra” activity.

This idea is supported by behavior change research, workplace productivity programs, and the practical experience of real people who have gone through this process. Here are a few suggestions to help you dedicate the time you need to achieve your health and fitness goals.

Before you begin. Any health behavior change should begin with identifying what you want to change, setting realistic goals, and determining what information, resources, and support you will need. For example, if you want to lose weight you should have a goal weight and timeline in mind. You should also set both short-term (weekly) and long-term (monthly or longer) goals.

This is also a good time to determine when and how you will put your plan into action. If you need information about what to eat or decide to join a gym to exercise, put those components in place now. Looking at your calendar and scheduling time for preparing meals and daily exercise or making a weekly menu of meals and a grocery list before you go to the store are good ways to invest your time.

Getting started. Once you have yourself organized, it is time to begin! Hopefully, this is a bit easier since you planned ahead, but keep in mind that you will continually need to revisit and modify your plan. This is important because a major reason why people don’t succeed is that they don’t allow flexibility in their plan. Once things go awry, they give up. The key is to keep moving forward, even if the progress is slow.

Keeping track of your weight or a record of what you eat or what you do for exercise is a simple way to monitor your progress. Linking progress to rewards is important for keeping you motivated, but make sure the rewards are consistent with your goals.

Sticking with it. While starting a diet or exercise program can be challenging, it is also exciting and seeing progress can be motivating. The trick is to maintain that progress over time, especially when you aren’t seeing such big improvements. Knowing that things will not always go as planned can help you avoid a bad day or week from ruining your success. This is why dedicating time to thinking about “what if” scenarios and coming up with back-up plans is essential.

 

The secret to lasting weight loss or maintaining an exercise program isn’t so much the details of the program but spending the time to plan, get off to a good start, and maintain the changes you decide to make. In the end, it’s about the time you dedicate to developing healthy habits.

 

 

Not sure where to begin to improve your health? A guide to taking the first step

If you are thinking about losing weight, becoming more active, or quitting smoking you are not alone. These are three of the most common health-related New Year’s resolutions. Considering that two-thirds of American adults are overweight, about half don’t meet minimum recommendations for physical activity, and one in five smoke, there are many people who need to change more than one of these behaviors.

Quitting smoking and changing eating and exercise habits to lose weight or improve fitness are among the most difficult behavior changes to make, especially at the same time. Some people focus on one change to begin with.

Obviously, changing all three of these behaviors is ideal, but if you are only willing to change one, which should you take on first to have the biggest impact on your overall health? This is the topic of my Health & Fitness column in the Aiken Standard this week.

You might think that quitting smoking would be the most important change to make initially. Smoking is the primary cause of lung cancer and other respiratory diseases such as emphysema and chronic bronchitis. Smoking also increases the risk of most other cancers and is a major contributor to heart attacks and strokes. Quitting smoking greatly reduces these risks with beneficial changes that begin within days of quitting. Despite this, if you only want to change one behavior, smoking isn’t the place to start.

Being overweight is a leading cause of diabetes, high blood pressure, heart disease, and some cancers. If you are overweight, losing just 10% of your body weight (20 lbs. for a 200 lb. person) can significantly reduce the severity of these conditions. Maintaining a healthy body weight can prevent many of these health problems. However, losing weight is not the first change you should make.

It turns out that becoming physically active is the most important change you can make to improve your overall health. Decades of research show that regular physical activity reduces the risk of most chronic diseases including diabetes, heart disease, and some cancers and can extend the lifespan by up to five years. In fact, the health risks of inactivity are equal to or greater than that of obesity or smoking. Regular activity also improves muscular strength, aerobic fitness, bone density, cognitive function, and memory. There is no other single intervention—drugs included—that has as many health benefits.

Research also shows that the negative health effects of being overweight and obesity are, in part, caused by inactivity and poor fitness. If you are overweight but physically fit, your risk of death is lower than if you are at a “healthy” weight but unfit. Regular exercise can reduce the risk of diabetes in people who are overweight, whether they lose weight or not. Furthermore, studies of “successful losers” show that daily exercise is a requirement for long-term weight loss, so becoming active now can help you lose weight later.

You should change all three of these behaviors to achieve optimal health. But if you are looking for an initial step that will have the biggest impact, start by becoming more active. A good initial goal is to reduce the time you spend being sedentary (sitting) and to get a minimum of 30 minutes of moderate-intensity activity, such as a brisk walk, each day. You can get greater benefits by participating in more intense exercise, including strength training, three or more days per week. And once you have established a routine of regular activity you will be ready to make other health changes.

Funny calorie math.

Have you ever heard that a few extra calories each day—an extra soda, for example—can add up to significant weight gain over time? Or that making small changes in what you eat, such as skipping dessert, can promote weight loss? If so, you are familiar with the concept of energy balance. And if you were ever surprised by those claims, you are familiar with what I call funny calorie math.

This is the topic of my Health & Fitness column in the Aiken Standard this week.

Your body weight at any time is determined by the balance between the energy you take in and the energy you expend. The “energy in” part is simple, it’s the calories in the food you eat.

Your energy expenditure is determined by your basal metabolic rate (BMR), the calories burned keeping you warm and alive, as well as the energy you expend in activity. Of these, the BMR accounts for the majority of your energy expenditure, but you have the most control over your level of activity.

According to this energy balance model, eating or drinking an additional 250 calories per day would add up to about one pound of weight gain every two weeks and 26 pounds after one year (using the rough estimate that to gain a pound requires 3500 extra calories.

+250 calories/day  x  7 days/week  =  1750 calories/week  =  3500 calories/2 weeks

3500 calories/2 weeks  x  1 lb. weight gain/3500 calories  =  1 lb. weight gain every two weeks  =  26 lbs. weight gain per year!

Calculations like this are common, typically used to point out how fattening a particular food or beverage can be. But the same principle can be applied in reverse to determine weight loss.

Example: Eat (or drink) and extra 250 calories per day

250 calories/day  x  7 days/week  =  1750 calories/week  =  3500 calories/2 weeks

3500 calories/2 weeks  x  1 lb. weight loss/3500 calories  =  1 lb. weight loss every two weeks  =  26 lbs. weight loss per year!

The same formula predicts that cutting back by 250 calories per day should lead to losing 26 pounds in one year. This idea is the basis for suggesting that making small changes to your diet can lead to significant weight loss over time.

You can do the same thing with physical activity, too. Adding a 45-minute walk, which burns approximately 250 calories, each day should lead to the same 26 pounds of weight loss in a year.

Example: walk 2.5 miles in 45 minutes each day, using the rough estimate that you will burn 100 calories per mile.

2.5 miles/day  x  100 calories/mile  =  250 calories/day

250 calories/day  x  7 days/week  =  1750 calories/week  =  3500 calories/2 weeks

3500 calories/2 weeks  x  1 lb. weight loss/3500 calories  =  1 lb. weight loss every two weeks  =  26 lbs. weight loss per year!

The assumption, of course, is that you aren’t changing anything else as you eat 250 fewer calories or burn an additional 250 calories per day through exercise. It would be relatively easy to offset the energy expended though a walk by even a small change in what you eat. This is the biggest weakness of this energy balance model—in order for it to accurately predict weight loss or gain, nothing else can change.

Unfortunately, this isn’t the way it really works. Changes in body weight through eating or exercise also lead to changes in total energy expenditure. As you lose weight, the total calories you burn in a day drops, mostly due to a decrease in BMR, since it is based on your body weight. The result is that over time you don’t lose weight as quickly. The exact opposite occurs with weight gain, which causes BMR to go up, limiting weight gain.

This leads to a different outcome: the extra 250 calories per day is likely to lead to a weight gain of closer to 10 pounds (maybe less) due to your BMR increasing as you gain weight over the year. And the estimation of weight loss will be different, too, given that BMR will drop slightly over time.

This is one of many reasons why exercise is important for weight loss. You can offset the lower BMR that occurs as you lose weight by increasing energy expenditure through activity. Additionally, regular exercise can add to the weight you lose through a diet and help keep the weight off later.

Why turning off your phone is so hard, and what it means for losing weight

I had an interesting conversation with one of my students recently about making a behavior change. It brought up a good point. So good, I wrote about it in my Health & Fitness column in the Aiken Standard this week.


One of the courses I am teaching right now is Health & Behavior Change. In it we identify the major factors that contribute to chronic disease and discuss how to modify them to improve health. Throughout the course, the emphasis is on health behaviors and how to change them for the better.

For example, smoking is among the most difficult health-related behaviors to change. Obviously, there is the addictive nature of nicotine that makes smoking cessation challenging. Beyond the drug effect, smoking also has a behavioral component. This includes what a smoker does first thing in the morning, after a meal, or on a work break as well as the act of holding a cigarette in his or her hand. Add to that the social aspects of smoking, including the influence of friends and family members, and it is easy to understand why it is a difficult habit to break.

This same principle applies to other health behaviors, including eating and activity. Like smoking, what we eat and our activity level are complex behaviors that are difficult to change. Because of this, losing weight can be as difficult as quitting smoking for similar biological and behavioral reasons. We think of weight loss as being about a diet or exercise program, but it’s really about changing behaviors and habits.

his is a difficult concept to teach, so I have my students learn through experience. Since almost all of my students are non-smokers and most are active and at a healthy body weight, I have them complete a project in which they change some other behavior. They are responsible for identifying a behavior that has a negative effect on their life, coming up with a plan to change it, and embarking on a four-week behavior change experience.

One student wanted to change her social media habits. As a compulsive social media user, she spent more hours than she realized checking, posting, and commenting on Facebook, Twitter, and other sites. Her goal was to limit her social media time so that it didn’t interfere with classes or studying. One of the steps she took was to turn off the notifications that alerted her to new activity. This was helpful, but she still found the habit of checking her phone hard to break.

In a conversation, she noted that the one thing that would help more than anything else would be to switch her phone off during the day. This way she would have her phone if she needed it, but it wouldn’t be so easy, or tempting, to use it. Despite knowing the most effective strategy—the one thing—that would help her, she never did it.

I thought this was an excellent example of something that is common in making health behavior changes. In many cases, people probably know the one thing they need to do to be successful but for a host of reasons, they don’t do it. This may lead people to make other changes that aren’t nearly as helpful. While even the smallest behavior modifications can help, successfully losing weight or quitting smoking really does require making big changes.

This goes a long way in explaining why quitting smoking, losing weight, and changing eating and activity behaviors can be so difficult, even when people know what they need to do. There is no easy solution for this problem, but finding someone to hold you accountable for making the necessary changes and sticking to them is a good start.

Don’t forget about breast cancer prevention!

October is National Breast Cancer Awareness Month and many local and national organizations are promoting breast cancer awareness, sharing information about the disease, and celebrating survivors. This month represents the most visible part of a year-round effort to educate about, screen for, and hopefully cure this devastating disease.

Of course, these are all worthy goals that deserve our attention and support. What is often missing are the steps women—especially young women—can take to reduce their risk for, or even prevent, breast cancer.

Approximately 1 in 8 women will develop breast cancer. The American Cancer Society estimates that around 300,000 new cases of breast cancer are diagnosed and nearly 40,000 women die from this disease each year. Breast cancer can occur in men, but these cases are rare, so the focus is rightfully on women.

Much attention is given to genetic factors that increase the risk of breast cancer. These include certain gene mutations, including BRCA1 and BRCA2, as well as family history. A woman who has a first-degree relative (mother, sister, or daughter) who has had breast cancer has nearly twice the risk of being diagnosed herself.

Considering that most women diagnosed with breast cancer have no family history, it is also important to try to reduce other modifiable risk factors. This involves making health behavior changes that are probably familiar to most people. The good news is that these changes can also reduce the risk of other cancers, cardiovascular disease, and most other chronic diseases.

Avoid tobacco use. While the results of studies of smoking and breast cancer are mixed, a conservative interpretation is that smoking may increase the risk. Smoking increases the risk of other cancers, especially lung cancer, as well as heart attack, stroke, and other lung diseases. Not smoking, or quitting now, is among the best health decisions a woman can make.

Consume alcohol in moderation. Women should limit their alcohol intake to one drink per day. Women who consume more than two drinks per day increase their risk of breast cancer by 20% over women who don’t drink.

Maintain a healthy body weight. Being overweight can increase the risk of breast cancer in post-menopausal women by 30–60%. Excess body fat can alter the levels of estrogen and other hormones. The good news is that losing as little as 10 pounds can reduce this risk.

Be physically active everyday. Regular activity and exercise can lower breast cancer risk by as much as 20%. In addition to helping with weight control, physical activity may lower the level of certain hormones that are associated with breast cancer. The biggest reduction in risk of breast cancer is seen in women who have been active their whole lives, but it is never too late to start.

Eat a healthy diet. The evidence from studies on the effect of diet on breast cancer risk is mixed, and more research is needed. In general, increasing fruit, vegetable, and whole grain intake and reducing red meat is associated with at least some decrease in breast cancer risk. These “healthy” foods are rich in vitamins, minerals, and other nutrients and eating more of these foods may lead to weight loss or prevent weight gain with age.

Every woman has a different breast cancer risk based on her unique family history, biology, and lifestyle. But by making some simple health behavior changes, all women can reduce their risk for, or even prevent, breast cancer and improve their overall health.

 

Loosening our belts. Expanding waistlines means expanding health problems.

In a report published this week, researchers showed that the waistlines of Americans are still expanding. This is bad news, since excess fat, especially around the waist, has serious implications for our health. Fortunately, there is much we can do to lose weight and improve our health.

This is the topic of my Health & Fitness column in the Aiken Standard this week.

The study, published in the Journal of the American Medical Association, looked at the percentage of adults who had a high waist circumference (over 35 inches for women and over 40 inches for men). Overall, the average American added over one inch to their waist circumference over the past decade. As of 2012, over half of U.S. adults (51%) meet the criteria for abdominal obesity, compared to 46% in 2000.

Since excess muscle tends to compress the abdomen, this really does reflect an increase in fat around the waist, not the benefits of a national sit-up campaign. And it is the location of the fat that makes this worrisome. Excess fat around the waist includes both subcutaneous fat beneath the skin (what you can pinch) as well as visceral fat stored deep in the abdomen.

Excess visceral fat is associated with an increased risk of high blood pressure, type 2 diabetes, and heart disease, among other chronic conditions. The only way to determine how much visceral fat a person has is through an imaging test like a CT scan. (In my lab we can estimate visceral fat by making a few abdominal measurements.) The important point is that the bigger your waist circumference, the more visceral fat you likely have.

You may have heard of people’s body shapes described as “apple” or “pear.” Upper body obesity (apple), sometimes called android obesity because it is more common among men, is associated with a high waist circumference and visceral fat. Lower body, or gynoid, obesity (pear shape) tends to involve a narrower waist but more fat storage in the hips, thighs, and buttocks.

These body shapes become apparent when you measure both waist and hip circumferences. A high ratio between waist and hip measurements indicates more upper body fat; a low waist-to-hip ratio suggests lower body fat. That said, just measuring your waist circumference can give you the same information. A waist measurement greater than 40 inches for men and 35 inches for women indicates excess upper body—and visceral—fat.

There is no single explanation for why waist circumference has increased so much in the population. But it almost certainly has to do with a combination of individual factors including what foods we eat, how much we eat, and how active we are. The average American with an expanding waistline likely eats too much poor quality food and doesn’t get enough exercise.

These are exactly the same factors that, when reversed, can lead to fat loss. Indeed, research shows that even modest weight loss from a low-calorie diet and exercise can result in reduced body fat, including visceral fat. This is one reason why weight loss is effective for reducing high blood pressure and controlling blood glucose.

Even if you don’t lose weight, increasing your level of physical activity, particularly regular exercise, can offset some of the negative health effects of excess visceral fat. In addition to helping you lose weight, exercise can also help you maintain your waistline and prevent abdominal obesity.

The bottom line is that when your pants start to feel tight, they are trying to tell you something. Listen to them!

Fat still matters

Last week I wrote about some recent research suggesting that low-carbohydrate diets may be better for weight loss that low-fat diets. For many, this study reinforced the notion that traditional recommendations are wrong and that the key to good health is to eliminate carbohydrates from your diet. This couldn’t be further from the truth.

The recent study did show that people lost more weight and experienced beneficial changes in blood lipids when they followed a low-carbohydrate diet compared to those who ate a low-fat diet. However, this does not mean that low-fat diets aren’t effective for weight loss or that they are “unhealthy.”

In fact, low-fat diets have long been used effectively to promote weight loss, reduce heart disease risk, and lead to healthier eating in general. This is supported by the results of hundreds of research studies as well as the practical experience of health professionals and real people. Here are two reasons why fat still matters when it comes to health.

First, reduced-fat diets have been shown to improve blood cholesterol and lower the risk for heart disease. Eating a diet low in fat, especially saturated and trans fat, has been the foundation of nutrition recommendations for decades. The fact is that these diets are effective for weight loss, reducing cholesterol, and otherwise improving heart health.

One famous study demonstrated that following a low-fat diet contributed to a reduction in the severity of atherosclerosis, the narrowing of arteries that leads to many heart attacks. Literally hundreds of other studies have shown similar beneficial results.

This isn’t some magical effect of eating less fat, though. The health benefits are likely due to eating more vegetables, fruits, and whole grains as much as they are to reducing fat intake. The point is that adopting a low-fat diet can lead to better nutrition overall.

Second, reducing fat intake is a good way to reduce calories. This is true because fat contains nine calories per gram, more than twice that of carbohydrates and protein, so cutting fat is an effective way to cut calories. Limiting fat intake also reduces calories indirectly because many high fat foods are also high in sugar and calories (think of most desserts).

It is important to mention that simply reducing fat intake won’t always lead to weight loss; total calories must be lower, too. This is a mistake many make when they reduce fat intake, but increase the amount of calories from other sources, typically carbohydrates. Many low-fat foods are actually relatively high in calories due to added sugar or people tend to eat more of them (the SnackWell Effect).

The effectiveness of low-fat diets for weight loss has been demonstrated in research studies (like this one) and countless weight loss programs. In one notable study, a diet low in fat even led to weight loss in people who weren’t trying to lose weight. And don’t forget that in the recent study about low-carbohydrate diets, the subjects that followed the low-fat diet also lost weight.

For some people, cutting carbohydrates as a way to lose weight is reasonable; for others, reducing fat intake makes sense. For most people, though, doing both to some extent is the best option, but going to extremes is unnecessary.

Eating less added sugar and avoiding foods with added fats (such as French fries) are good recommendations for almost everyone. That said, there is little evidence for the benefit of limiting carbohydrates in the form of whole grains, legumes, vegetables, and fruits or the fat in meat and dairy.

The bottom line is that the quality of food we eat is more important than the specific amounts of the nutrients it contains. Eating low-carbohydrate or low-fat diets can help steer you toward making healthier choices, but so can avoiding processed foods in favor of wholesome, nutrient-dense “real” food.

Good sources of protein for your low-carb diet

Thanks to a recent study and media coverage (including me), low-carbohydrate diets are a popular topic of discussion. For many people, cutting back on carbohydrates is a good way to reduce calories to promote weight loss.

Most low-carbohydrate diets also emphasize protein intake. But finding healthy protein sources is important for promoting weight loss and good health.

This recent discussion about the best protein for optimal weight loss  on the Train Your Body show on RadioMD should help.

The diet wars continue

If you are confused or frustrated by the conflicting claims about whether a low-fat or low-carbohydrate diet is the best, you are forgiven. First we were told that eating a low-fat diet was the best way to lose weight and improve heart health. Then, research suggested that low-carbohydrate diets were better. And back and forth it has gone for years.

During this time, the prevailing recommendations have suggested that a diet low in fat and high in carbohydrates was best. But more and more research has supported the notion that cutting carbohydrates, not fat, would lead to greater weight loss. Although this has been supported by some research, critics pointed out that eating more fat would raise blood cholesterol and other risks for heart disease.

According to a recent study, though, low-carbohydrate diets seem to have benefits for promoting weight loss and improving some indicators of heart health over low-fat diets. But you should hold off on shunning fruits and vegetables in favor of cheeseburgers! Here is a practical interpretation of the research and some common sense recommendations, taken from my Health & Fitness column in the Aiken Standard this week.

The study, published last week in the Annals of Internal Medicine, reported on 150 men and women who either restricted the amount of carbohydrates or fat they ate. After one year, the group that ate a low carbohydrate diet lost over 7 pounds more than the subjects on the low-fat diet. Additionally, the low-carbohydrate diet promoted greater improvements in blood lipids than the low-fat diet.

This is important for two reasons. First, this wasn’t a weight loss study; the researchers were simply following the subjects to see what would happen as they followed either diet. The fact that the low-carbohydrate group lost more weight suggests that it is relatively easier to cut calories following this type of diet.

This is consistent with other research showing that eating more carbohydrates, especially refined carbohydrates and sugar, can actually make people feel hungrier and eat more. Indeed, other studies have shown low-carbohydrate diets to be more effective for weight loss than low-fat diets (although a more recent study suggests there isn’t such a difference).

Second, the greater decrease in triglycerides and “bad” LDL cholesterol and increase in “good” HDL cholesterol in the low-carbohydrate group were different from what might be expected. Conventional wisdom holds that a low-fat diet should have a greater effect on blood lipids. Since weight loss can have a big effect on blood lipids, the improvement in the low-carbohydrate group may be due to losing more weight, not a direct effect of the diet.

It is important to note that the low-fat diet also led to weight loss in this and numerous other studies. The critical component of any weight loss diet is that it is relatively low in calories, regardless of what nutrients supply those calories. Really, almost any diet will lead to weight loss as long as it contains less energy than what is expended, but a low-carbohydrate diet may be more effective for weight loss than the traditional low-fat diet.

The bottom line is that the best diet is one that emphasizes eating wholesome foods, not on cutting carbohydrates or fat. That said, limiting carbohydrates in the form of refined grains and added sugar is an excellent way to reduce calorie intake and improve the overall nutritional value of what you eat. And shifting toward more monounsaturated fats (think olive oil and nuts) rather than worrying about the total amount of fat you eat is also a good idea.