The 800 Calorie Diet Plan and Its Weight Loss Benefits

The 800-calorie diet plan, also known as the Fast 800, is a very low-calorie diet (VLCD) that has gained popularity in recent years for its promise of quick weight loss. But is this restrictive eating approach safe and effective in the long run? Let’s take an in-depth look at the 800-calorie diet plan and what it entails.

What Is the 800-Calorie Diet?

Developed by Dr. Michael Mosley, the 800-calorie diet plan involves drastically cutting calorie intake to just 800 per day. The goal is to trigger rapid weight loss and metabolic benefits by putting the body into a state of ketosis, where it starts burning stored fat for fuel.

How does the 800-calorie diet work?

By severely limiting calories to 800 per day, the body is forced to tap into its fat reserves for energy. This metabolic shift can lead to significant weight loss in a short period of time, though much of the initial loss is water weight.

The 800-calorie diet plan is typically divided into two phases.

Rapid Weight Loss Phase (2–12 weeks): Consume 800 calories per day to jumpstart weight loss and metabolic changes.

Maintenance Phase: Gradually increase calorie intake to a more sustainable level while adopting healthy eating habits for long-term weight management.

What do you eat for 800 calories a day?

An 800-calorie diet plan focuses on lean proteins, non-starchy vegetables, and small amounts of healthy fats. A sample menu might include:

  • Breakfast: spinach and feta omelet
  • Lunch: Grilled chicken salad with mixed greens, tomatoes, and balsamic dressing
  • Dinner: Baked cod with roasted broccoli and quinoa
  • Snacks: Greek yogurt, berries, or a small handful of almonds.

It’s crucial to choose nutrient-dense foods to meet your body’s needs within the calorie limit.

Is the Fast 800 effective for weight loss?

Research has shown that very low-calorie diets, like the 800-calorie diet plan, can indeed lead to rapid weight loss in the short term. However, the long-term sustainability and safety of such restrictive approaches are often questioned by health professionals.

How Much Weight Will You Lose on 800 Calories a Day?

Weight loss on the 800-calorie diet plan varies, but most people can expect to lose around 2–4 pounds per week during the initial phase. Keep in mind that individual results may differ, and this rate of loss may not be healthy or sustainable for everyone.

Is the Fast 800 diet safe to follow in the long term?

The 800-calorie diet plan is designed as a short-term intervention, not a long-term solution. Extended periods of extreme calorie restriction can lead to nutrient deficiencies, muscle loss, metabolic adaptations, and other health risks. It’s essential to transition to a more balanced, sustainable eating pattern after the initial rapid weight loss phase.

What is the evidence for the Fast 800?

While some studies support the potential benefits of very low-calorie diets for weight loss and metabolic health, more research is needed to establish the specific efficacy and safety of the 800-calorie diet plan. Critics argue that the evidence is limited and that such extreme restrictions may do more harm than good in the long run.

Is the Fast 800 healthy? A Nutritionist’s Perspective

As a nutritionist, I advise caution when considering the 800-calorie diet plan. While rapid weight loss can be motivating, it’s not always healthy or sustainable. Severe calorie restriction can lead to nutrient imbalances, fatigue, irritability, and disordered eating patterns. In most cases, a more moderate approach focused on whole foods, portion control, and regular physical activity is a safer bet for lasting weight management.

Who Shouldn’t Follow the Fast 800 Diet?

The 800-calorie diet plan is not appropriate for everyone. You should avoid this approach if you are:

  • Pregnant or breastfeeding
  • Under 18 years old
  • Struggling with an eating disorder or a history of disordered eating
  • Dealing with certain medical conditions (e.g., diabetes, heart disease) without doctor supervision
  • Underweight or have a low body mass index (BMI).

Always consult with a healthcare professional before starting any new diet, especially one as restrictive as the 800-calorie diet plan.

Can I eat 800 calories a day for a month?

Following the 800-calorie diet plan for a full month without medical supervision is not advisable. Extended periods of severe calorie restriction can be dangerous and may lead to nutrient deficiencies, electrolyte imbalances, gallstones, and other complications. If you’re considering this approach, work closely with a doctor to ensure safety and appropriateness.

Is 800 calories per meal good?

No, consuming 800 calories in a single meal is not a balanced approach. Eating that many calories in one sitting can lead to blood sugar spikes, energy crashes, and feelings of deprivation later in the day. It’s generally better to spread your calorie intake evenly across several smaller meals and snacks to maintain stable energy and satiety.

The Bottom Line of the 800-Calorie Diet Plan

While the 800-calorie diet plan may yield rapid weight-loss results in the short term, it’s a highly restrictive approach that comes with potential risks. Severe calorie restriction can lead to nutrient deficiencies, muscle loss, metabolic slowdown, and rebound weight gain. For most people, a more moderate, sustainable eating pattern combined with regular physical activity is a healthier path to lasting weight management. If you’re considering the 800-calorie diet plan, consult with a healthcare professional to weigh the pros and cons for your unique situation.

FAQ

Is the 800-calorie diet plan safe for everyone?

No, the 800-calorie diet plan is not safe or appropriate for all individuals. Pregnant women, teenagers, people with certain medical conditions, those with a history of eating disorders, and anyone who is underweight or has a low BMI should avoid this restrictive approach.

Can I follow the Fast 800 without medical supervision?

It’s strongly advised not to attempt the 800-calorie diet plan without guidance from a healthcare professional. Severe calorie restriction can be dangerous and may not provide adequate nutrition for your individual needs. Medical supervision can help ensure safety and appropriateness.

How long can I stay on the 800-calorie diet plan?

The duration of the 800-calorie diet plan varies, but it’s generally not recommended to follow this approach for more than 12 weeks. Extended periods of extreme calorie restriction can lead to adverse health effects. It’s crucial to transition to a more balanced, sustainable eating pattern for long-term weight maintenance.

Will I regain weight after stopping the 800-calorie diet plan?

There is a risk of weight gain after discontinuing the 800-calorie diet plan if you don’t have a solid plan for transitioning to a balanced, sustainable way of eating. Severe calorie restriction can slow your metabolism, making it harder to maintain weight loss. Adopting healthy, long-term eating and exercise habits is key to preventing rebound weight gain.

Are there any side effects of the 800-calorie diet plan?

Potential side effects of the 800-calorie diet plan include fatigue, irritability, dizziness, constipation, nutrient deficiencies, muscle loss, hair loss, gallstones, and menstrual irregularities in women. Some people may also experience disordered eating patterns or an unhealthy preoccupation with food due to the restrictive nature of the diet.

Key Takeaways from the 800-Calorie Diet Plan

  • The 800-calorie diet plan is a very low-calorie approach that involves consuming just 800 calories per day to promote rapid weight loss.
  • By severely restricting calories, the body enters ketosis and starts burning fat for fuel, leading to quick weight loss in the short term.
  • An 800-calorie diet plan focuses on lean proteins, non-starchy vegetables, and small amounts of healthy fats to meet nutrient needs within the calorie limit.
  • While effective for fast weight loss, the 800-calorie diet plan comes with risks, including nutrient deficiencies, muscle loss, metabolic slowdown, and rebound weight gain.
  • The 800-calorie diet plan is not safe or appropriate for everyone, especially pregnant women, teenagers, individuals with certain medical conditions, and those with a history of eating disorders.
  • For most people, a more moderate, balanced approach to eating combined with regular physical activity is a healthier, more sustainable path to weight management.
  • If you’re considering the 800-calorie diet plan, it’s crucial to work with a healthcare professional to ensure safety and appropriateness for your individual needs and medical history.

References

  1. https://thefast800.com/
  2. https://www.healthline.com/nutrition/ketosis-and-weight-loss
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4018593/
  4. https://www.verywellfit.com/how-much-weight-can-i-lose-on-an-800-calorie-diet-3495284
  5. https://www.medicalnewstoday.com/articles/322345
  6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5959807/
  7. https://www.nhs.uk/live-well/healthy-weight/start-the-nhs-weight-loss-plan/
  8. https://www.healthline.com/nutrition/calorie-restriction-risks
  9. https://www.mayoclinic.org/healthy-lifestyle/weight-loss/in-depth/calories/art-20048065