17 Day Diet Review: Does It Work for Weight Loss?

The key to this diet is changing your food combinations and calorie intake each 17-day cycle.

Dr. Moreno believes that changing your diet in this way prevents boredom and keeps your metabolism in a state of “confusion” to speed up weight loss and avoid plateaus.

However, many claims associated with this diet are not supported by quality studies.

This article reviews whether the 17 Day Diet can help you lose weight.

DIET REVIEW SCORECARD

• Overall score: 2.63
• Weight loss: 3.25
• Healthy eating: 4
• Sustainability: 1.75
• Whole body health: 1.75
• Nutrition quality: 3
• Evidence based: 2

BOTTOM LINE: The 17 Day Diet aids weight loss by restricting calories and food groups. However, this diet makes many questionable claims and rules that are unsupported by good scientific studies.

The 17 Day Diet was created by Dr. Mike Moreno and his book first published in 2010.

It’s suggested to help you lose weight rapidly and build healthy eating habits. The key to this diet is constantly changing foods and calorie intake, which is claimed to boost your metabolism (1).

The 17 Day Diet is divided into four cycles: Accelerate, Activate, Achieve and Arrive. The first three cycles last 17 days each, while the Arrive cycle is meant to be followed for life.

As you move through the cycles, the diet introduces new strategies and food options.

It’s worth noting that the diet does not tell you how many calories to eat during each cycle. However, it progressively increases your calorie intake by introducing more calorie-rich options with each cycle.

In 2014, Dr. Moreno released a “breakthrough edition” of the diet with a few additions:

• More recipes and food options.
• Contour foods to help you target fat loss in specific areas.
• Optional fast day between cycles.
• Supplements for the 17 Day Diet.
• 17-minute workout to target fat loss in specific areas.

Here are the four cycles of the 17 Day Diet.

Cycle 1: Accelerate

The first cycle of the 17 Day Diet is the Accelerate cycle.

It claims to help you lose 10–12 pounds (4.5–5.4 kg) over the first 17 days by (1):

• Increasing your protein intake.
• Improving digestive health.
• Reducing sugar, sweets and refined carbs.
• Clearing your body of possible toxins that affect your metabolism.

During this phase, you’re allowed to eat unlimited protein and vegetable options from the specified Accelerate foods list. Most carb-rich foods are banned during this cycle.

However, fruits are an exception — though you’re not allowed to eat any fruit after 2 p.m. The book claims that it is harder to burn carbs later in the day, as you’re less active.

Other guidelines to follow include:

• Purchase skinless poultry or remove the skin.
• Avoid alcohol and sugar to improve digestion.
• Consume two probiotic foods daily to promote digestive health.
• Eat slowly and chew thoroughly until you feel full.
• Drink eight 8-ounce (240-ml) glasses of water each day.
• Exercise at least 17 minutes per day.

Cycle 2: Activate

The second cycle of the 17 Day Diet is the Activate cycle.

During this cycle, you alternate between lower- and higher-calorie days.

On lower-calorie days, you simply eat as you would during the Accelerate cycle. On higher-calorie days, you can add two servings of naturally higher-starch carbs, such as legumes, grains, tubers and root vegetables.

To follow this cycle, spend one day on the Accelerate plan, the next day on the Activate plan. Continue to alternate between these two versions over the next 17 days.

This second cycle is based on the idea of alternate-day fasting. However, it takes a modified approach, as its lower-calorie days are higher in calories than on a traditional alternate-day fasting diet.

In addition, the Activate cycle adds plenty of new food options.

This cycle is claimed to help reset your metabolism, but evidence to support this is lacking.

Many rules form the Accelerate cycle still apply, such as not to eat carbs after 2 p.m. This means that you must eat your carb options with breakfast and lunch during this second cycle.

Cycle 3: Achieve

The third cycle of the 17 Day Diet is the Achieve cycle.

This cycle aims to establish healthy eating habits with steady, manageable weight loss. Alternate-day fasting is no longer required and the diet is similar to the Activate days of the second cycle.

You are now allowed to eat a wider variety of carb sources, such as breads, pastas, high-fiber cereals and virtually any fresh fruit or vegetable.

In addition, you may drink one optional glass of alcohol per day if you would like. However, the diet advises passing on the alcohol if you want more weight loss.

Since you’re eating more food than in previous cycles, it’s recommended to increase aerobic exercise from the minimum 17 minutes to 45–60 minutes per day.

It’s worth noting that it’s still not permissible to eat carbs after 2 p.m. during this cycle.

Cycle 4: Arrive

The last cycle of the 17 Day Diet is the Arrive cycle.

Unlike other cycles — that all last 17 days — this cycle is meant to be followed for life.

For this phase, you may choose any meal plan from either of the three previous stages — Accelerate, Activate, Achieve — and follow them from Monday breakfast to Friday lunch.

From Friday dinner through Sunday dinner you can enjoy your favorite foods in moderation. However, you’re advised not to eat more than one to three of your favorite meals over the weekend.

In addition, you can drink one to two alcoholic beverages daily over the weekend.

It’s recommended to get in at least an hour of intense exercise on Saturday and Sunday since you consume more calories on the weekends.

During this cycle, it’s still suggested to not eat carbs after 2 p.m.

Summary

The 17 Day Diet has three fat-loss cycles — Accelerate, Activate and Achieve — which last 17 days each. The final cycle is called Arrive and is a lifetime weight maintenance plan.

One of the biggest draws of the 17 Day Diet is that it can help you lose weight quickly, as it restricts calories — which means you’re creating a calorie deficit.

Consuming fewer calories than your body burns is a surefire way to lose weight (2, 3, 4).

For instance, during the Accelerate cycle, the 17 Day Diet limits your choices to lean proteins, non-starchy vegetables and probiotic foods — which are low in calories.

During the Activate phase, it implements a modified take on alternate-day fasting, which has been found to be effective for fat loss, as people find it easy to follow (5, 6).

Still, though the diet can aid weight loss, it makes various weight loss claims that are unsupported by evidence, such as that the change in food groups and calorie intake can “confuse” and boost your metabolism.

It also recommends avoiding carbs after 2 p.m., claiming that carbs eaten later in the day are harder for your body to burn, as you burn less energy in the evening. However, there are no high-quality studies that support this claim.

All told, the 17 Day Diet can help you lose weight, but evidence to suggest that it is more effective than conventional, calorie-restricted, whole-foods diets is insufficient.

Summary

The 17 Day Diet can help you lose weight, as it encourages calorie restriction and alternate-day fasting, which are techniques supported by science. Yet, it also makes bold claims and recommendations that are not evidence-based.

In addition to weight loss, the 17 Day Diet offers other potential benefits:

• Vegetarian- and vegan-friendly: This diet has plenty of options that allow it to be followed by vegetarians and vegans.
• Gluten-free-friendly: It can be made gluten-free.
• Caters to many cuisines: It has options for Mediterranean, Hispanic, Indian, Asian and many other cuisines, making it region-friendly.
• High in fiber: It advocates eating plenty of high-fiber foods. Fiber may not only aid weight loss but also offers many other health benefits (7, 8, 9).
• Has tips on surviving difficult situations: The program provides helpful tips on eating out, surviving holidays and family situations — all of which can be tricky.

Summary

In addition to weight loss, the 17 Day Diet offers other potential benefits, such as catering to a variety of cuisines and lifestyles. It’s also high in fiber and provides tips on how to survive difficult situations that typically affect people on a diet.

Though the 17 Day Diet offers many potential benefits, it has several drawbacks as well:

• Supported by weak evidence: Evidence to support many claims associated with this diet is insufficient. This includes the notion that the diet can “confuse” your metabolism or the rule to avoid carbs after 2 p.m.
• May affect workout performance: The first two cycles of the 17 Day Diet are lower in calories and carbs, which may have a negative impact on exercise.
• Cost of supplements: In the breakthrough edition of the 17 Day Diet, Dr. Mike Moreno introduces supplements, which can be expensive. For instance, “Dr. Mike’s 17 Day Diet Pack” costs $69.88 for roughly a one-month supply.
• Easy to fall off track during the last cycle: During the last cycle, you’re allowed the freedom to eat your favorite meals three times per week. However, it can be easy to overeat or binge on weekends — negating achieved weight loss.

Summary

Though the 17 Day Diet has various potential benefits, many claims and rules are supported by weak evidence. Plus, it may compromise workout performance, the cost of supplements can be expensive, and the last cycle makes it is easy to fall off track.

The 17 Day Diet has four cycles, each with a unique list of food options.

Foods to eat during the Accelerate cycle

• Fish: Salmon (canned or fresh), catfish, tilapia, flounder, sole, canned light tuna in water.
• Poultry: Chicken and turkey breast, lean ground turkey, eggs, egg whites.
• Non-starchy vegetables: Cauliflower, cabbage, broccoli, Brussels sprouts, green leafy vegetables, tomatoes, okra, onions, carrots, bell peppers, cucumber, celery, eggplant, garlic, green beans, leeks, mushrooms, etc.
• Low-sugar fruits: Apples, oranges, berries (all), peaches, grapefruit, pears, plums, prunes, prickly pear cactus, red grapes.
• Probiotic foods: Sugar-free, fruit-flavored, plain and low-fat yogurt (such as Greek-style), Yakult, kefir, low-fat acidophilus milk, tempeh, reduced-salt miso, kimchi.
• Oils: Olive and flaxseed oil.
• Condiments: Salsa, light soy sauce, fat-free sour cream, Truvia, sugar-free jams, vegetable cooking spray, vinegar, fat-free salad dressings, salt, pepper, mustard, all herbs and spices, low-carb ketchup and marinara sauce.

It’s worth mentioning that you can only choose eggs as a protein option twice per week.

Serving sizes may vary and some foods are restricted to a certain number of servings per day. For example, you may eat only two servings of low-sugar fruits and probiotic foods per day.

Foods to eat during the Activate cycle

In addition to the Accelerate options, you can add the following options during the Activate cycle:

• Shellfish: Crabs, clams, oysters, mussels, scallops, shrimp.
• Beef (lean cuts): Flank, top sirloin, top round, eye of the round, round tip, top loin, lean ground beef.
• Pork (lean cuts): Sirloin chops, boneless loin roast and top or center loin chops.
• Lamb (lean cuts): Shanks and sirloin roast.
• Veal (lean cuts): Cutlet.
• Grains: Amaranth, barley (pearled), quinoa, bulgur, couscous, brown rice, cream of wheat, grits, basmati rice, millet oat bran, old-fashioned oatmeal.
• Legumes: Black beans, black-eyed peas, butter beans, garbanzo beans (chickpeas), great northern beans, kidney beans, lentils, lima beans (baby), navy beans, peas, pinto beans, soybeans, split peas.
• Starchy vegetables: Breadfruit, potato, sweet potato, corn, taro, winter squash, yam.

Grains, legumes and starchy vegetables can only be consumed on activate days, and one serving of grains and legumes is a 1/2 cup cooked.

Foods to eat During the Achieve cycle

During the Achieve cycle, you may choose any foods from the previous two cycles, plus the options below:

• Meats: Cornish hen, quail pheasant, Canadian bacon and reduced-fat turkey bacon, sausage or lunch meat.
• Breads: Cracked-wheat, fiber-enriched, gluten-free, multi-grain, oat-bran, sugar-free, pumpernickel or rye bread, pita pocket, whole-wheat tortilla, whole-grain bagel.
• High-fiber cereals: All-Bran, All-Bran Extra, All-Bran Buds, Fiber One, gluten-free cold cereals, low-sugar granola.
• Pasta and noodles: Whole-wheat pasta, gluten-free pasta, vegetable-based pasta, high-fiber pasta, udon noodles.
• Vegetables: Virtually any vegetable, including alfalfa, broccoli sprouts, chilis, cilantro, fennel, jicama, pea pods, radishes, rhubarb, rutabaga, summer squash, swiss chard, zucchini, kelp and other edible seaweeds, etc.
• Fruits: Virtually any fresh fruit, including bananas, cherries, apricots, currants, figs, kiwi, mango, guava, papaya, pineapple, tangerine, tangelo, etc.
• Low-calorie cheeses: Brie, Camembert, Fontina, low-fat cheddar, Edam, feta, goat, Limburger, part-skim mozzarella, low-fat cottage cheese, low-fat ricotta cheese.
• Milks: Low-fat milk, sugar-free rice milk, almond milk, soy milk.
• Oils: Canola and walnut oil.
• Condiments: Light mayonnaise, mayonnaise, reduced-fat salad dressings.
• Other fat options: Raw nuts or seeds, avocado, reduced-calorie margarines, trans-fat-free margarine.
• Optional snacks: Frozen fruit bar, Fudgesicle (100-calorie bar), granola bar (reduced-sugar and -fat), light microwave popcorn, Skinny Cow ice cream sandwich, sugar-free pudding cup.
• Alcohol (1 drink per day): 5 ounces (150 ml) of wine, 12 ounces (355 ml) of beer, 1.5 ounces (45 ml) of hard liquor.

Foods to eat During the Arrive cycle

The Arrive cycle allows all of the food options mentioned above with the option of eating three of your favorite meals from Friday dinner to Sunday dinner.

You’re also allowed the following:

• One to two alcoholic drinks on weekends.
• The option to swap main meals for broth-based soups.
• The option to substitute one fruit serving for a 3/4 cup (180 ml) of unsweetened fruit juice or 1 cup (240 ml) of vegetable juice.

Summary

The 17 Day Diet becomes progressively less restrictive through its four cycles and reintroduces many staple foods, such as legumes, grains, pastas, breads and others.

Here is a one-day sample menu for each cycle of the 17 Day Diet.

Accelerate cycle

• Breakfast: 6 ounces (170 grams) of plain, low-fat yogurt, 1 cup (150 grams) of berries and 1 cup (240 ml) of green tea.
• Lunch: Grilled chicken breast with tossed salad drizzled with 2 tablespoons (30 ml) of balsamic vinegar.
• Dinner: Grilled or baked chicken with steamed vegetables and 1 cup (240 ml) of green tea.
• Snacks: 1 fruit of your choice and 1 serving of a probiotic food of your choice.

Activate cycle

• Breakfast: 1/2 cup (230 grams) of cooked oatmeal, 4 scrambled egg whites, 1 peach and 1 cup (240 ml) of green tea.
• Lunch: Shrimp salad drizzled with 2 tablespoons (30 ml) of balsamic vinegar, 1 medium baked sweet potato and 1 cup (240 ml) of green tea.
• Dinner: Pork sirloin chops (broiled or grilled), steamed veggies and 1 cup (240 ml) of green tea.
• Snacks: 1 cup (150 grams) of blueberries and 1 cup (240 ml) of kefir.

Achieve cycle

• Breakfast: 1 slice of whole-wheat toast, 1 boiled egg, 1 cup (150 grams) of berries and 1 cup (240 ml) of green tea.
• Lunch: Tuna sandwich, 1 pear and 1 cup (240 ml) of green tea.
• Dinner: Sesame fish, steamed vegetables of your choice and 1 cup (240 ml) of green tea.
• Snacks: 1 frozen fruit bar and 6 ounces (170 grams) of yogurt.

Arrive cycle (Friday)

• Breakfast: 2 poached eggs, 1 pear and 1 cup (240 ml) of green tea.
• Lunch: Baked turkey breast, a fresh garden salad drizzled with 1 tablespoon (15 ml) of flaxseed oil, 6 ounces (170 grams) of yogurt and 1 cup (240 ml) of green tea.
• Dinner: Dinner out with friends; for example, vegetable lasagna, tossed salad with blue cheese dressing, two 5-ounce (150-ml) glasses of red wine and 1 serving of tiramisu.
• Snacks: 1 apple and 1 cup (240 ml) of acidophilus milk or 6 ounces (170 grams) of yogurt.

Summary

The above menus provide you with an idea of what a typical day at each cycle of the 17 Day Diet is like.

The 17 Day Diet is a weight loss program that promises quick results by switching up your food combinations and calorie intake through different cycles.

It aids weight loss by encouraging whole, unprocessed foods and exercise. Yet, many of its claims and rules are not supported by high-quality scientific evidence.

What’s more, its effectiveness at maintaining weight loss is questionable, as it involves life-long dieting.

Instead, adopting healthy habits — such as simply eating whole foods, limiting refined sugar and exercising regularly — may be more effective for maintaining weight loss in the long run.