The drawbacks: What if the suggested diet for your blood type eliminates foods that you like and has you eating foods that you don't?
The skinny: Evidence fails to support any benefit to this type of nutrition plan. This diet does emphasize a plant-based diet and promotes exercise, and these are important components of a healthy diet.
More: The Pros and Cons of a Vegetarian Diet
Alkaline Diet
The limitations: The Alkaline Diet is based on the idea that what you eat impacts the pH level of your blood. This diet emphasizes vegetables, fruits, nuts and legumes. It discourages the consumption of meat, poultry, fish, dairy products, processed foods, white sugar and white flour. It also limits caffeine and alcohol.
More: 10 Ways to Find Hidden Sugar in Your Diet
The skinny: When our bodies are healthy, they regulate blood pH very efficiently on their own. If your blood pH is not within its normal range (7.35 to 7.45), this is a sign of a larger issue to be addressed with a doctor, and is not a dietary issue.
The Fast Diet
The limitations: The Fast Diet is based on the concept of 5:2 intermittent fasting, meaning you eat normally for five days of the week and pick two consecutive days to limit calories to a quarter of normal intake (500 calories for women and 600 for men). On the fasting days, the focus is on a combination of lean protein and low-glycemic foods. Success also depends on not overeating on the normal days.
More: How Glycemic Index Affects What You Should Eat Before and During a Race
The drawbacks: There is not enough research yet to support that fasting has any benefits to our health. Historically, fasting can make a person irritable, cause daytime sleepiness or sleeplessness at night, and can even lead to dehydration.
More: 8 Tips for Hydrating in Cold Weather
The skinny: Fasting may not be right for certain populations—for example, diabetics, pregnant or breastfeeding women, those recovering from surgery or an illness. This practice is not the best option for very physically active individuals.
For long-lasting results, your best diet plan is to consume healthy, well-balanced meals that contain fruits and vegetables, whole grains, and lean sources of protein, while also making exercise a part of your daily routine. This will not only make you healthier, but you will also feel better. This approach is sustainable long-term, and won't be something that will fail to be effective.
More: 11 Simple, Realistic Ways to Improve Your Diet
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