How the 15-day body reset diet works, what you eat in each phase, and what research on low-calorie diets, meal replacements and weight regain says about it.
The body reset diet is a 15-day weight loss plan created by celebrity trainer Harley Pasternak. It replaces most meals with homemade smoothies at first, then gradually brings back solid food, alongside daily walking and short resistance workouts (1).
The plan’s premise is that fast early results keep people motivated. The diet itself has not been studied in published research (1), so this guide looks at the evidence behind its main parts.
Key Takeaways
- The plan has three five-day phases that move from three smoothies a day to one smoothie and two solid meals (1).
- It provides roughly 1,200 to 1,400 calories a day (1).
- Meal replacement programs led to slightly more weight loss at one year than other diets in a meta-analysis of 23 trials (3).
- Appetite hormones and lower energy use after dieting make weight regain common (6).
- The 10,000-step target is higher than the level where mortality benefits leveled off in older adults (12).
What Is the Body Reset Diet?
Pasternak, who has a background in exercise physiology and nutritional science, set out the plan in The Body Reset Diet and a companion cookbook. You eat five times a day: smoothies, snacks and, later, simple single-dish meals made from specific recipes (1).
- Smoothies: about 270 to 325 calories each. They are named white, red and green after their color, and combine a liquid base (water or low-fat or plant milk), protein (protein powder, tofu or fat-free yogurt), a healthy fat (avocado, nuts or seeds) and high-fiber fruit or leafy greens. Added sweeteners are not allowed (1).
- Snacks: about 150 calories, low in sugar, with at least 5 grams of protein and 5 grams of fiber, such as edamame, air-popped popcorn or celery with peanut butter (1).
- Meals: 230 to 565 calories, such as salads, sandwiches on whole grain bread, soups, stir-fries and egg white scrambles (1).
- Avoided for 15 days: full-fat dairy, refined grains, fried and highly processed foods, sugary drinks and alcohol. Only calorie-free drinks are allowed (1).
The Three Phases of the Body Reset Diet
Save| Phase | Meals each day | Exercise |
|---|---|---|
| Phase 1 (days 1–5) | 3 smoothies + 2 snacks | At least 10,000 steps a day |
| Phase 2 (days 6–10) | 2 smoothies + 1 solid meal + 2 snacks | 10,000 steps a day; 5 minutes of resistance training (4 exercises) on 3 days |
| Phase 3 (days 11–15) | 1 smoothie + 2 solid meals + 2 snacks | 10,000 steps and 5 minutes of resistance training every day |
| After day 15 | Phase 3 pattern + 2 “free meals” a week | Continue the routine |
Source: plan summary from Healthline (1).
People who weigh over 175 pounds (79 kg) may increase smoothie portions by one-third. After day 15 there is no official end point: you continue the phase 3 pattern and add two “free meals” a week, meant to prevent feelings of deprivation (1).
Does the Body Reset Diet Work for Weight Loss?
The plan itself has no trial behind it, so the only honest way to judge it is part by part. Each row below is a piece of the plan set against the research on that piece.
| The part of the plan | What the research actually shows | Source |
|---|---|---|
| Meal replacements (the smoothies) | A systematic review of 23 trials in 7,884 adults found slightly more weight loss at one year than comparison diets — though only 6 of the 23 were judged at low risk of bias | (3) |
| 1,200 to 1,400 calories a day | In a 12-week trial that randomised 302 adults, calorie restriction lowered BMI by 1.3 kg/m² against 0.6 in the control group | (5) |
| Keeping the weight off afterwards | Appetite hormones and lower energy expenditure after dieting make regain common | (6) |
| Nutrients at that calorie level | An analysis of three commercial plans found shortfalls including vitamin D and calcium — though two of its authors worked for a supplement company | (8) |
| 10,000 steps a day | Across 15 cohorts and 47,471 adults the benefit levelled off at 6,000 to 8,000 steps in adults 60 and older, and 8,000 to 10,000 in younger ones | (12) |
| The diet as a whole | Never tested in a clinical trial of its own | (1) |
At 1,200 to 1,400 calories a day plus daily walking, most adults will eat fewer calories than they burn, so short-term weight loss is likely (1). In a 12-week randomized trial of 302 adults with overweight or obesity, a calorie-restricted diet lowered BMI by 1.3 kg/m², compared with 0.6 kg/m² in the control group, although low-carbohydrate diets lowered it further (5).
Research on meal replacements is also relevant. A meta-analysis of 23 trials with 7,884 adults found that programs using meal replacements led to about 1.4 kg more weight loss at one year than other diets, and more with extra support; some authors held research grants from a meal replacement company (3). Another meta-analysis found the greatest effect when meal replacements supplied at least 60% of daily energy (4). Those studies mostly used commercial shakes, not homemade smoothies.
Adherence matters most. A review of dietary weight loss studies concluded that how well people stick with a diet, rather than the type of diet, is a key factor in success (2).
What Happens After Day 15?
Weight regain is the main challenge of any calorie-restricted plan. After calorie intake is cut, the body lowers its metabolic rate and increases the drive to eat, and appetite-stimulating hormones can stay raised a year after dieting (6). In a meta-analysis of US weight loss programs, people who followed balanced low-calorie diets had kept off about 17% of the weight they lost, in studies that followed people for two to five years (7). Groups who exercised more kept off more weight (7).
The plan’s answer is to stay on the phase 3 pattern long term. Whether that works depends on whether you can follow it comfortably. If you want a less structured approach, see our guide to low-calorie diets and menus.
Pros and Cons
Pros
- The plan is built on whole foods such as fruits, vegetables, whole grains, legumes, nuts and lean protein, the foods at the center of healthy eating patterns (1, 9).
- It is high in fiber. Higher fiber intake is linked to lower risk of heart disease, type 2 diabetes and some cancers, and to lower body weight (10); fiber also supports gut motility (11). See our list of high-fiber foods.
- Walking and short strength sessions are part of the plan. For a longer routine, see our dumbbell workout plan.
Cons
- The calorie level is low for many adults and can make it hard to meet nutrient needs (1). An analysis of three commercial diet plans found shortfalls in several vitamins and minerals, including vitamin D and calcium; two authors worked for a supplement company (8).
- Liquid meals may be less filling than solid food, and hunger is a common reason people drop out of weight loss plans (1).
- The diet has not been tested in its own clinical trial (1).
Is 10,000 Steps a Day Necessary?
A meta-analysis of 15 international cohorts with 47,471 adults noted that there was little evidence behind the 10,000-step target. More steps were linked to lower mortality, but the benefit leveled off at about 6,000 to 8,000 steps a day in adults 60 and older and 8,000 to 10,000 steps in younger adults (12). Walking more is still useful, especially for keeping weight off (7).
Who Should Check With a Doctor First
SaveTalk to a doctor or registered dietitian before starting a plan this low in calories if you:
- have diabetes or take medication that lowers blood sugar or blood pressure
- have heart, kidney or other chronic disease
- have a history of an eating disorder
- are pregnant or breastfeeding
- are under 18
For a similar short plan and its limits, see our review of the 3-day diet.
Frequently Asked Questions
How much weight can you lose on the body reset diet?
The body reset diet itself has not been tested in a published study, so there is no reliable figure. It provides about 1,200 to 1,400 calories a day, which creates a calorie deficit for most adults, but weight loss varies with age, sex, body size and activity.
How many calories are in the body reset diet?
About 1,200 to 1,400 calories a day. Recipes in the book give roughly 270 to 325 calories per smoothie, about 150 calories per snack and 230 to 565 calories per solid meal. People over 175 pounds (79 kg) may increase smoothie portions by one-third.
What can you eat on the body reset diet?
Homemade smoothies made with a liquid base, protein, healthy fat and high-fiber fruit or leafy greens, snacks with at least 5 grams of protein and fiber, and simple meals such as salads, sandwiches, soups, stir-fries and egg white scrambles. Full-fat dairy, refined grains, fried and highly processed foods, sugary drinks and alcohol are avoided during the first 15 days.
Do you have to walk 10,000 steps a day?
The plan sets a target of 10,000 steps a day. A meta-analysis of 15 cohorts found that more daily steps were linked to lower mortality, with the benefit leveling off at about 6,000 to 8,000 steps in adults 60 and older and 8,000 to 10,000 steps in younger adults.
Can you keep doing the body reset diet after 15 days?
Yes. The plan is meant to continue in the phase 3 pattern, with one smoothie, two solid meals, two snacks and two free meals a week. Research shows that sticking with a diet matters more than which diet you choose, so long-term success depends on whether this pattern suits you.
The Bottom Line
The body reset diet is a structured 15-day plan of smoothies, high-fiber snacks and simple meals at about 1,200 to 1,400 calories a day, plus daily walking and short strength workouts. It will likely lead to short-term weight loss, and meal replacement research suggests this kind of structure can help. The plan itself has not been studied, calorie restriction triggers changes that favor regain, and the low intake may leave nutrient gaps. It may suit healthy adults who want a clear short-term structure, as long as they plan how they will eat after day 15.
This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting a low-calorie diet or new exercise program.
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