Fat vs. fiction: What diets work?

Lose 15 pounds by the weekend? Get your dream body while eating whatever you want and without having to go to the gym? Shelves full of books and hours of infomercials will try to have you believe otherwise, but there is no magic formula that can get you the body you want.

Yes, losing weight can be a daunting task - which explains the appeal of programs that promise to make weight loss easy. But all too often, fad diets result not only in regaining lost pounds, but in putting on extra weight as well. That's because safe, effective and, most importantly, long-term weight loss requires two important things:

  • permanent changes in the way you eat
  • making exercise a habit, not just something you do on the rare occasion that the mood strikes

And these are two things that many quick fixes fail to incorporate.

Here are some tips for recognizing fad diets or weight loss gimmicks:

  • It promises unrealistic results. Safe weight loss means no more than 2 lbs. (1 kg) per week. If you lose weight any faster than that, your body could compensate by slowing down the rate at which it burns calories, thereby slowing weight loss and even making it easier to gain weight after you return to your normal eating habits.
  • It requires you to purchase special products, supplements, or foods. The foods you need to lose weight sensibly - a balance of fruits, vegetables, whole grains, lean meats, and lower-fat dairy products - are all available at the grocery store.
  • It eliminates certain foods or even whole food groups entirely. By cutting out certain foods from your diet, you risk coming up short on all the vitamins and nutrients you need.
  • It requires you to strictly follow a set plan. The less a diet plan takes into account your own personal likes and dislikes as well as your lifestyle, the less likely you are to stick to it. Any diet plan you follow should also account for your individual nutritional requirements, which can vary depending on age, activity level, and any medical conditions.

Here are some qualities of reliable diet plans:

  • They incorporate exercise. Burning energy through exercise means you can achieve weight loss without having to cut the number of calories you consume as drastically. As well, studies have shown regular exercise is one of the biggest predictors of keeping the weight off.
  • They make recommendations based on sound science. A safe weight-loss program makes its claims based on large-scale studies that have been reviewed by reputable health care professionals.
  • They meet Health Canada's daily recommended intakes. It's important to make sure you are getting all the protein, vitamins, and minerals you need. Because it can be difficult to meet your targets while restricting calories, your doctor or dietitian may recommend supplements. To help you out, check out Canada's Food Guide for tips on responsible eating and recommended caloric intake. Find it at www.hc-sc.gc.ca/fn-an/food-guide-aliment/index-eng.php
  • They include plans for maintenance. Your program should help you form the habits you need to make your weight-loss long term. Remember, healthy eating is a way of life - not just a two-week plan.

What's the problem with quick weight loss?

Being overweight has been shown to take a considerable toll on our health, from upping our risk of heart disease to diabetes to some forms of cancer. So you'd think it would be wise to lose weight any way you can. But losing weight on an unsafe diet plan or repeatedly losing and gaining weight, as can happen as a result of fad dieting, can also cause health problems.

The vicious cycle of losing and gaining weight is often referred to as yo-yo dieting. While some people may tell you yo-yo dieting can make it harder to lose weight the next time around, a number of studies have shown that to be a myth. But that doesn't mean yo-yo dieting is good for you.

One study that was published in the Journal of the American Dietetic Association suggests that yo-yo dieting may weaken the immune system. The study, which measured immunity by testing the activity of natural killer cells - which fight off viruses such as the common cold, viral pneumonia, herpes, and more - found that postmenopausal women who had ever intentionally lost at least 10 lbs. had weaker immune systems. And the more times the participants had lost 10 or more pounds, the greater the effect. Women who lost weight and kept it off, however, seemed to have stronger immune systems.

There is also some evidence that yo-yo dieting may increase your risk of developing high blood pressure and gallstones. But while many experts say the risks associated with yo-yo dieting shouldn't stop you from trying to lose weight if you are overweight, they do underscore the importance of finding a weight-loss plan that will help you not only lose the fat, but keep it off as well.

And yo-yo dieting aside, fad diets can have other negative effects on your health. For example, many fad diets are effective for quick, short-term weight loss because they require a very low-calorie diet, which has been linked to gallstones in obese patients.

Cutting out particular foods or severely cutting calories may also limit the vitamins, nutrients, and minerals you get from dietary sources, causing a nutritional deficiency. Even if you are losing weight on a more reliable diet plan, you should talk to your doctor, pharmacist or a registered dietitian about whether you need any vitamin supplements.

Carbs be gone?

One day they're in, the next day they're out again. But whether we're talking about Atkins or South Beach, low-carb diets are one kind of fad that never seems to die.

If you haven't tried a low-carb diet, you may not know that many of these programs restrict all kinds of carbohydrates, and not just the obvious ones, such as bread, rice, and pasta. For example, Atkins, perhaps the best-known low-carb diet around, also excludes most grains, beans, fruits, potatoes, and starchy vegetables, while allowing lots of beef, pork, chicken, eggs, and butter.

Low-carb diets work because when you consume low levels of carbohydrate, your body has to resort to burning stored carbohydrates (glycogen) in order to fuel itself. Then your body starts to burn stored fat, resulting in a process called ketosis. Ketosis is what happens when the body burns fat without carbohydrate, resulting in the buildup in the bloodstream of a by-product called ketones. Ketones suppress appetite but may also cause you to feel tired or nauseous.

In theory, low-carb diets sound like a great way to lose weight. One study found a low-fat, low-carb, high-protein diet to be as effective for weight loss as a low-fat, high-carb, low-protein diet. Both diets also lowered blood cholesterol and insulin, but the patients on the low-carb diet reported less hunger and more satisfaction.

It is important to note, however, that the diet in this study differed from the popular Atkins, which is high in fat. But another study which compared an Atkins-style diet to a low-calorie, low-fat, high-carbohydrate diet found that subjects on the Atkins-style plan initially lost more weight and had a greater increase in HDL or "good" cholesterol than those on the high-carb plan. After one year, however, weight loss for both groups was similar, and subjects on both diets were equally likely to drop out.

But while being able to eat all the steak, butter, and eggs you want and still lose weight may sound like a great plan, there is a downside: A diet that's rich in meat and high in fat can take a toll on your health.

One recent study, published in the Journal of the American Medical Association, suggested that eating lots of red meat over a prolonged period is associated with a higher risk of colorectal cancer. Because of the increased strain so much meat puts on your kidneys, low-carb diets can also increase your risk of kidney stones and may deplete your calcium levels, putting you at risk for osteoporosis. You may also be at increased risk of developing gout.

And while the Atkins diet was shown to raise HDL levels in the short term, so far there is no research on how this diet - which is high in cholesterol-promoting saturated fat - affects heart health in the long term. As well, because this diet cuts out so many foods that provide vital nutrients - things like whole grains, fruits and veggies - it's important to think about the long-term effect this could have on your ability to fight other diseases.

The losing formula for your weight

Sure there's no magic bullet for easy weight loss. But the winning - er, losing - formula isn't as complicated as you may think.

Here are some strategies for successful weight loss:

  • Set a realistic goal. Weight loss is yet another example of slow and steady winning the race. Rather than trying to drop a size by tomorrow, set a goal of 1 to 2 pounds (no more than 1 kg) per week. Keep in mind that it takes a deficit of 3,500 calories to lose a pound - so to meet this goal, aim to cut 500 to 1,000 calories a day through a combination of diet and exercise.
  • Talk to your doctor or a registered dietitian. They can help you set a realistic target weight and tailor a plan to your own likes, dislikes, and nutritional needs. They can also provide support, help you find strategies for dealing with setbacks and obstacles, and monitor your progress and health as you lose weight.
  • Eat a balanced diet. Follow Eating Well with Canada's Food Guide and make sure to get a balance of whole grains, fruits, vegetables, lean meats, and lower-fat dairy products. Strive for variety to make sure that you get all the nutrients you need and you don't get bored with your diet.
  • Work in a workout. Regular aerobic exercise burns calories, making it easier to meet your weight loss goal. Strength training can also help you lose weight by increasing your muscle mass - muscle tissue burns more calories than fat, even when you're at rest. And remember: Every bit counts. If you don't always have enough time for a full workout, you can burn calories by taking the stairs, not the elevator, and choosing a parking spot further away from the shopping mall doors.
  • Take everything in moderation. If you cut the foods you love out of your diet altogether, you're only setting yourself up for an eventual binge. So enjoy a treat once in a while, but keep the serving size small. And if you fall off the wagon, remember: eating well is a lifestyle, so instead of giving up, just get back with the program as soon as possible.