What: Based on the notion that the foods you eat react chemically with your blood type.
Why: Proponents of this diet claim that by following a diet designed specifically for your blood type, your body digests and absorbs food more efficiently, resulting in weight loss, more energy and prevention of disease.
Why not: In the long term, eliminating major food groups can result in a poor intake of nutrients needed for good health. Cutting out dairy products, for example, can lead to poor intakes of calcium and vitamin D, which can put you at risk of osteoporosis, while avoiding meat can result in low intakes of iron, which can lead to anemia. And there's no scientific proof that your blood type affects weight loss.
What: This diet recommends consuming alkaline forming foods (vegetables, fruit, nuts, seeds) and eliminating or limiting acid forming foods (meat, poultry, fish, dairy, grains, salt, sugar, caffeine, alcohol and artificial and processed foods).
Why: The premise is that foods that make the body acidic can lead to: weight gain, osteoporosis, arthritis, diabetes, heart disease and even cancer. This diet often leads to weight loss, as it emphasizes fresh produce while eliminating processed foods.
Why not: Our bodies are incredibly efficient at keeping our pH within normal range, so cutting out specific foods will not affect your body's pH. The diet is strict, complicated and bans foods that can have a place in a healthy eating plan, such as meat, dairy and grains.
What: A liquid-only diet consisting of: lemon juice, maple syrup and cayenne pepper mixed in water. Lasts for up to 10 days.
Why: The diet claims you’ll drop pounds, detoxify your digestive system and feel energetic, vital, happy, and healthy. You’ll also curb cravings for unhealthy food.
Why not: There is no scientific evidence that the diet removes any toxins, or that it achieves anything beyond temporary weight loss. And the weight you lose will be mostly water, so once you start eating solid foods again, you’ll likely gain all the weight back. Plus, consuming an extremely low amount of calories can cause loss of not just fat, but muscle too. Common side effects include dehydration, fatigue, nausea and dizziness.
What: Also known as the Stone Age and Hunter-Gatherer Diet, this regime recommends eating as our ancestors did 10,000 years ago. That means foods that can be hunted, fished or gathered: meat, fish, shellfish, poultry, eggs, vegetables, fruits and berries. Grains, dairy, legumes (beans or peas), sugar, salt and alcohol are not allowed.
Why: Proponents of this diet claim that our bodies are genetically predisposed to eat this way. The combination of plant foods and a diet rich in protein can help control blood sugar, regulate blood pressure, contribute to weight loss and prevent Type 2 diabetes.
Why not: Although avoiding processed foods is a good thing, this diet is excessive with protein, saturated fat and lacking in carbohydrates, fiber and in some nutrients including calcium and vitamin D. This diet is very rigid and can be difficult to follow.
What: Eliminate all sources of gluten, a protein found mainly in wheat, barley, rye and a few other related grains. This diet was specifically created for people whose bodies are negatively affected by gluten (Celiac Disease).
Why: Since the most common sources of gluten include high-calorie items like bread, pasta, rice, sweets and other snack foods, the avoidance of these foods often leads to weight loss. Some people feel that they have a sensitivity to gluten (Non-Celiac Gluten Sensitivity): bloating, abdominal discomfort or pain, constipation and diarrhea. Research in this area is conflicting and it is unclear as to whether or not these symptoms may be a result of gluten, or certain types of carbohydrates in foods, such as lactose or fructose.
Why not: It's not the elimination of gluten causing weight loss – it's the consumption of fewer calories and processed foods overall. If you don't have celiac disease, or a sensitivity, you do not need to eat gluten free. Also, keep in mind that many of the gluten-free options use more refined grains (lower in fibre), have extra sugar and aren't as rich in nutrients.
Looking for a diet that's right for you? We detail the latest weight-loss fads
New fad diet books are constantly flooding the marketplace, promising to tell us the secret answers to losing weight. Turn on the television or radio, open a magazine or walk through your local grocery store and you'll be exposed to the latest diet fads. It's easy to flock to diets that promise fast results with little effort.
Unfortunately, there really is no such thing as a quick fix, and most health experts don't recommend fad diets. The best diet is not a diet at all, but a way of life that includes food you enjoy, exercise, and healthy habits. It may not be glamorous, but it really is that simple.
The following diets might spur weight loss in the short-term, but beware, many are difficult to follow, have wishy-washy rules, and a few could be detrimental to your health.
Carolyn is a registered dietitian and a self-proclaimed foodie with a passion for cooking and experimenting in the kitchen. Carolyn works in a variety of areas including clinical nutrition, sports nutrition, private practice, and in the media. She is a contributing writer for Huffington Post BC and HealthCastle. Using her whole foods approach to health, Carolyn writes her own food blog; check out her blog Wealth of Health. Carolyn is passionate about empowering people with knowledge about nutrition so that they can make the best decisions to improve their health.