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Fit For Life Review - 24 Things You Need to Know

This review is what happened after I obsessed for weeks over Fit for Life. Our research team focused on the Fit for Life foods and meals, potential side effects of this eating plan and scientific studies supporting the claims. Finally, we summarized all of the pertinent data to give you the facts.

Fit For Life can be purchased through their Official Site.

Fit For Life Readers: Noom is offering our readers a free trial, for a limited time. Click here for this special offer!

What is Fit For Life?

Harvey Diamond’s Fit for Life is a diet plan developed by Harvey and Marilyn Diamond.

The diet is formulated on the concept that eating a certain combination of food promotes good health. It also prohibits eating certain types of food altogether.

The diet primarily encourages eating whole grains and gradually eliminating refined grains and other processed food from your diet.

Food and exercise are the two important aspects of healthy living. You are what you eat, so when you decide to get Fit for Life, you should research the many diet plans which are currently on the market.

We have compiled a complete analysis of Fit for Life to help you understand the science behind the program along with the food combining chart and meal plan.

Take your time to read this article before you follow this popular but controversial diet plan.

Fit For Life Competitors

Paleo Diet

How Did Fit For Life Start?

The Fit for Life diet plan is inspired by the Nature Cure movement and rooted in Orthopathy or Natural Hygiene.

It was started by Harvey Diamond and his wife, Marilyn Diamond who also authored the book, ‘Fit for Life‘. The diet is based on the couples’ exploration of the principle of food combining as explained by the theories of Herbert M. Shelton.

The Diamonds also categorized food as either ‘dead food’ (highly refined) which harms the body or ‘living food’ (raw vegetables and fruits) which rejuvenate and cleanse the body.

Based on this principle, they came up with the Fit for Life program.

Fit For Life diet plan

The Basic Ideas For Harvey Diamond Fit For Life Diet Plan

This diet is all about the good and bad combinations of food. ‘Dead’ food should be completely avoided.

Diamond believed that the wrong combination of food can cause the food to ‘ferment’ in the stomach. Here are the main points of the diet plan.

Dairy products can cause allergies and should be consumed rarely, if at all. They are not considered to contribute valuable nutrition.

Water should never be consumed during meals because it would dilute digestive juices.

Fruits should be eaten raw and fresh. They should be eaten alone without other food.

It is ill-advised to combine proteins with carbohydrates during meals.

The dietary principle involves consuming predominantly ‘live’ food with high water content.

When animal protein is eaten, it must not be eaten with complex carbohydrates. Fit for Life recipes Harvey Diamond offers let us see what this diet offers each day.

Fit For Life Harvey Diamond – Breakfast

A typical breakfast in Fit for Life meal plan would consist of carbohydrates. They can be eaten alone or with vegetables.

Carbohydrates should not be consumed with animal protein foods such as milk, butter, or cream.

They should also not be consumed with fruits. There should be a profusion of whole grain (bread, muffin, bagel) in the servings. Fit for Life’s food combination chart gives us an idea of the foods that should and should not be combined.

Fit For Life Recipes – Lunch

Lunch can be enjoyed in two different ways: by combining protein with vegetables or combining carbohydrates with vegetables. Combining proteins and carbohydrates in one meal is strongly discouraged.

For example, you could have carbohydrates in whole wheat bread with bean sprouts, grated carrots and add some lettuce, or steamed brown rice with stir-fried vegetables.

Protein foods will have vegetable salads with chickpeas (garbanzo beans) or red kidney beans and sunflower seeds. You might relish a steaming cup of lentil soup with a variety of vegetables and a drizzle of light oil-based dressings instead of milk or cream.

Fit For Life dinners

Fit For Life Food Combining Dinner

While breakfast and lunch are carbohydrate-loaded meals, Fit for Life diet recommends high-protein dinners. Diamond advises against animal proteins (except for organic eggs and fresh fish).

Some of the Fit for Life recipes for dinner include vegetarian chili with beans and lentils, or assorted vegetable and legume curry or stew.

Other stable dishes are stir-fried tofu with Asian vegetables, raw salad vegetables, and steamed asparagus.

Dairy Products In Fit For Life

Drinking milk or eating other dairy products such as butter, cheese, yogurt, pudding, cottage cheese, etc. is prohibited by Fit for Life diet program.

The reason is that the human digestive tract is not designed to digest dairy products properly. This could lead to a number of problems such as allergies, IBS (Irritable Bowel Syndrome), or even Crohn’s disease.

To alleviate this problem, Diamond offers a supplement. The USDA asserts that dairy products are the main source of calcium and recommends adults to have up to 3 cups of dairy products per day.

Dairy also supplies protein.

Fit For Life fruit

Fruits In Fit For Life Meal Plan

Fruits must be eaten alone or consumed as juice but never with other food. The diet also suggests that fruits be consumed early in the morning, not in afternoon.

This is because fruits have digestive enzymes with cleansing properties. It is very beneficial to eat them and activate the digestive system, according to Advances in Nutrition.

Fit For Life Book

The Fit for Life book by Harvey and Marilyn Diamond explains the diet and lifestyle. This diet became popular in the 1980s and was a New York Times bestseller, selling millions of copies.

Through the book, Diamonds urged people to reject chemical additives and hydrogenated vegetable oil (popularized at that time as an alternative to butter). They advocated for veganism to increase energy levels.


Fit For Life Claims

Fit for Life Harvey and Marilyn Diamond claim that following their diet plan Fit for Life, will cause weight loss and prevent obsessions with counting calories and exercising vigorously.

A reasonable exercise schedule with the Fit for Life meal plan can help you get Fit for Life. In fact, Diamond claimed that mixing different foods can cause fermentation which would kill valuable nutrients and enzymes.

In the 2000s, the Diamonds launched FFL’s Weight Management Program which uses genetic predisposition, metabolic typing, and “analyzation” to create a Personalized FFL.

This Fit For Life meal plan can be used for each individual throughout his or her life. In this version, there was no more talk of ‘dead’ and ‘living,’ but the emphasis was on enzyme-rich or enzyme-deficient foods.

They promptly began selling enzyme supplements called as nutritional supplements.

Fit For Life whole grains


Fit For Life Ingredients

The Harvey Diamond Fit for Life diet recipes is mostly made of unprocessed whole foods.

The strategies of combining certain groups of food are not proven to improve health and have no strong scientific basis. The diet chiefly consists of:

  • Whole-grain foods
  • Legumes
  • Beans
  • Raw fruits and vegetables
  • Fresh fish
  • Organic eggs
  • Vegetable oils and seasoning
  • Food with high water content

Does Fit For Life Work?

This diet focuses on lifestyle changes and eating habits. Because Fit for Life by Harvey Diamond and Merilyn Diamond was published several decades ago, several happy people have lost weight.

However, it remains unknown whether or not these people succeeded in losing weight because of the authors’ insights or merely because of restrictions on their calorie intake.

Many have nothing but praise for the book and the authors but there are many others from the realm of nutrition and health have reservations about supporting this diet which promises weight-loss.

There are people who still consider it a fad, albeit one that has stood the test of time.

Benefits & Results

Fit For Life Benefits And Results

Though widely known as a diet for weight loss without causing adverse effects, Fit for Life is much more than just a diet program.

It is actually a healthier way of living. Unlike the many crash diets that cause you to lose weight drastically but bounce back to your original weight in a trice, Fit for Life by Harvey Diamond does not cause this yo-yo effect.

After the initial days of perpetual hunger pangs, you will get used to (and even look forward to) short and frequent snack breaks. Healthy eating and proper hydration result in weight loss.

Fit For Life results

Details On Fit For Life And Weight Loss

The fundamental principle of this diet plan states that just by eating more amounts of the right type of food, you can alter your life, get into shape, and live happily.

The plan entails adhering to your body’s natural cycles of digestion, assimilation, and excretion and eliminating highly refined grains from your diet.

Fit For Life 24

This is a premier all-week and all-day fitness center that offers free nutrition programs with a low membership fee of barely $10 per month.

The center offers the most diverse fixed and free weights and has the widest variety of equipment which includes flat benches, squat racks, and many more.

Fit for Life 24 is the go-to fitness center for those who yearn to be Fit for Life.

How To Diet With Fit For Life

The first step is to divide your day into three phases or time pockets. When you adhere to this natural cycle of life, your body works best and everything else falls into place. Noon to 8 pm is the time for eating food and its digestion.

8 p.m. to 4 a.m. is the time for assimilation when your body absorbs and uses. 4 a.m. to noon is the elimination of waste. Once you follow this pattern, you can get Fit for Life.

Fit For Life foods list

FFL Food List

The Good And The Bad FFL Food

FFL promotes eating fruit by itself earlier in the day when your stomach is empty. You must wait 30 minutes before you consume any other food.

Proteins should be eaten as a main course in combination with a large helping of vegetables as a side dish. Starches can also be eaten as a main course with vegetables.

Oils, animal fats, and dairy products cause indigestion, weight gain, and are likely to ferment in the stomach. Seed oils and nut butter are preferred.

Non-starchy fruits and vegetables with high water content and fiber such as zucchini, squash, cucumber, collards, lettuce, cabbage, parsley, okra, beet greens, kale, asparagus, tomatoes, sweet peppers, and broccoli are recommended.

Garlic, leeks, shallots, radishes, and onions are considered irritants and should be used sparingly.

Food Combining Chart

Fit For Life Food Combining Chart

The idea behind combining varieties of food is to complement nutritive values. Diamond strongly believed in this.

It is the basis for the Fit for Life food combining chart. Although the concept itself was around for decades, the Fit for Life book by Harvey Diamond served to popularize it.

This chart is a perfect guide for people who wish to learn which food combinations will work for them. Health Authority has a food combination chart.

The Fit for Life diet plan works around the food combining chart and natural body cycle.

Consequently, there is a restriction on what can be eaten and at what time of the day. The diet eschews the consumption of dairy products, animal protein, and processed food.

The diet also advocates certain combinations of food.

Diamond believed that when food was properly combined to promote good digestion, it will result in weight loss and also body energization.

Side Effects

Side Effects Of Fit For Life Diet Plan

One of the most obvious side effects is the overwhelming pangs of hunger.

The diet requires you to start the day with a bowl of serving of fruits. With a breakfast of a bowl of fruits, you will be counting minutes for the mid-morning snack, a whole wheat bagel or another bowl of fruit.

There are specific kinds of food which can be in combination, so the choice is quite limited. As a result, this diet can leave you feeling perpetually hungry, tired, and constantly looking forward to the next meal.

Fit For Life warnings


Fit For Life Diet Plan Warnings

The first complaint of skeptics is the lack of sound scientific backing for some of the diet’s rules. Eating healthy whole grains and fresh produce is a welcoming start, but there are many claims which lack proof.

This is probably because the authors lack expertise in this field. They don’t have the educational qualification, or training, or personal experience to validate their claims in the book.

This amounts to dishonesty and there was a lawsuit in this regard. There is no sound scientific proof for many of their claims.

Any Fit For Life Lawsuits?

As previously stated, there are speculations about the authenticity of the claims made by Fit for Life’s Harvey Diamond and Marilyn Diamond due to their lack of qualifications.

The doctorate degree he obtained from a University of questionable credentials was proved to be bogus.

Two decades after their book shot them to celebrity status, and a divorce later, Harvey Diamond and his son were in court again with his other son, Beau Diamond who faced Ponzi scheme charges, reports the Sarasota Herald-Tribune.

There is no trace of documented lawsuits against the controversial diet plan.

Reception To Fit For Life Diet Plan By Scientists

Health experts and nutritionists have scant regard for the book by Diamonds and have dismissed it as sheer quackery. Not only are Harvey Diamond’s credentials widely disputed, but many of the book’s claims have also been questioned by the scientific community.

The ideas propounded in the FFL diet have heavy leanings to alternative medicine, especially on theories of how our bodies work. Some of the ideas are not acceptable by conventional medicine and others totally contradict scientific research, as the book Complementary and Alternative Medicine in the United States reports.

Fit For Life alternatives

Fit For Life Alternatives

The diet plan is similar to many plant-based, low calorie, high-protein diets and discourages the consumption of processed food.

This was a revolutionary idea at that time but there are several current meal plans and diets where people are more aware and conscious of their health and food habits.

The following diets could be regarded as alternatives to the FFL diet plan:

The Seven-Day Hay Diet

This is based on combining certain foods and avoiding foods which can increase acidity levels in your system and hinder the digestion process.

Three- Day Fruit And Vegetable Diet

This is a detox diet that is prescribed to cleansing your system. Vegetables and fruits are rich in fiber, antioxidants, vitamins, and minerals and can help reduce the risk of heart problems, obesity, diabetes, and even cancer. This is followed only for three days, then a normal diet is resumed.

Two-Week Vegan Meal Plan

This is for those who are considering turning vegan or for die-hard vegans who want to try new delicacies.

What Users Are Saying

“I’ve studied health and diet for 50 years. This is one of the best books on the subject. What’s important about diet is not only what we eat, but when and in what combinations. Do not eat breakfast!”

“I read this back in the 80s when it first came out, and I wasn’t overly impressed. I just re-read it for interest, and nothing has improved. My criticism is that this book has very little scientific evidence in it. Instead what you will receive is a whole series of arguments regarding why a particular food or practice is beneficial. Arguments are fine if you’re reading philosophy, but I don’t want to hear arguments in a diet book. I just want scientific evidence.”

“90% of what is written in the book as helpful advice has been proven by multiple scientific journals and studies to be either not helpful at all or in some cases even detrimental. It’s a book that basically buys a little into every popular diet fad from the past. Huge waste of money, if you eat a balanced diet and exercise moderately you will end up 10x healthier than you would following the advise in this book. Please save the $7 and spend it on a gym membership.”

Bottom Line

The Bottom Line On Fit For Life

What’s the real deal with the Fit for Life diet? The program has numerous glowing reviews from people who have successfully lost weight. However, the science indicates that these individuals lost weight due to calorie restrictions rather than through any valuable insights. According to authorities in the field of health and nutrition, this is little more than a fad diet which is why we have reservations about giving it our support. It’s also expensive and the price and food list are only visible once you sign up which feels shady.

If you are ready to lose weight we suggest sticking with a diet plan that was created with careful study and is strongly backed by the medical community. You may want to try a weight-loss program that uses a unique set of methods that are backed by solid scientific testing and strong customer support.

Among the best programs we’ve seen this year is called Noom. The program combines the latest in weight-loss and tracking technology with human coaching and personalized meal plans to create a customized weight-loss plan. During our research, we didn’t find any negative online reviews. What we did find was glowing commentary from happy customers who successfully lost excess weight.

The makers of Noom are so excited about their product that they are now offering a free trial, which many dieters have begun taking advantage of.

Learn More About Noom »
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Fit For Life

What is the Fit For Life diet?

The Fit For Life Diet is a series of books that point to healthy eating practices, such as, eating mainly living and high-water-content foods, having fruit all by itself for breakfast, and not mixing animal proteins with complex carbohydrates when eating them. The series is marketed by Marilyn and Harvey Diamond, which are two American authors. They both maintain that staying fit for life is easy if you follow seven specific habits, which include not depriving yourself, not making excuses, walking more, choosing activities that make you move, making your workouts shorter, discovering ways of making your vegetables more enjoyable, and making sleep a top priority in your life.

What are the ingredients in the Fit for Life Diet?

The ingredients for the Fit for Life Diet is fruit for breakfast. Animal proteins must not be consumed in conjunction with complex carbohydrates. Meat is limited. One is instructed to eat live food instead of dead food. Dead food is said to be food cooked to over a certain temperature, usually over 108 degrees. One should not eat foods from a can. White bread is not allowed. Vinegar in salad dressing is not allowed. Raw onions and garlic must be limited. Limit carbohydrates.

What are the side effects of the Fit for Life Diet?

The side effects of the Fit for Life Diet can be summed up in the side effects that the food modifications required by the diet may cause. Examples of these side effects may include Vitamin B12 deficiency due to one limiting animal proteins via the diet. Low energy may be experienced from the limited carbohydrates.

Does the Fit for Life Diet work?

The Fit for Life Diet does work. The diet may not be for everyone as with most things, yet the Fit for Life Diet does work for some. There is a solution for every person.

What is the price of the Fit for Life Diet?

A new copy of The Fit for Life book written by the authors Harvey Diamond and Marilyn Diamond can currently be purchased for $13.04. The book that guides you through the Fit for Life Diet can also be purchased used for $1.33.

Where can I buy Fit For Life?

Fit For Life can be purchased using their Official Site.

Where can I buy the Fit for Life Diet?

The Fit for Life Diet book can be purchased at Amazon.com and at BN.com. Simply do a search on each website for Fit for Life.

How should I take the Fit for Life Diet?

One should take the Fit for Life Diet slowly. This will allow the body to adjust to the changes in the variations of food consumption recommended by the diet.

How do I contact the Fit for Life Diet customer service?

While direct contact can only be made via the book, one can always search Youtube.com for Harvey Diamond and Marilyn Diamond. This will bring up more in-depth information and opinions on the diet.

Can I return the Fit for Life Diet book?

Yes the Fit for Life Diet book can be returned yet the information that you receive can literally change your life if the information obtained is applied.

What are the most common complaints about the Fit for Life Diet?

The most complaints about the diet are by far the deficiency of Vitamin B-12 in the body which means dips in energy. Other minor complaints are meal preparations for busy people due to the limited combinations of foods that are allowed. The most minor complaint is finding a location to eat out at restaurants again due to the food combinations allowed by the diet. All of the complaints are said to be minor due to the good results that the diet provides.

23 Fit For Life Reviews

  • Jaz

    im 13 and I have done the fit for life now for about 5-6 months and I’m not losing any weight I’m just putting more on (6 kg ) and I’m felling really hungry because there is very little protean in this diet I’m not sure if this just me but if someone knows the a answer to why this is happening could you please reply?

    • Adrian (Editor)

      Hi Jaz. Please make sure to consult with your physician before continuing this product to make sure its safe and effective for you to use.

    • Baylee

      Probably because at the age 13 your body weight is supposed to fluctuate like crazy. You gain weight and then get taller. Girly, go eat a cheeseburger.

    • Maria

      Please please please do not go on a diet this young. Your body is still changing.

  • It works !
    janie ramirez (Verified Purchase)

    my husband and I did this diet and it works

  • Harvey diamond loves you

    For any questions that you want to ask Harvey, if you are on facebook, type in “harvey diamond loves you”, and it will take you to his page. He always answers any questions.

    • Jeannie

      I am thinking about going on Fit for life diet. I don’t have to lose any weight but am looking for help with digesting my food and would like help with my mental clarity. Has anyone have benefited from following this diet in these areas? Thank you for you responding to answering my request to my question.

      • Sharon

        Yes, it’s main goal is to make suggestion easier on your body. I have IBS & heartburn, but when I follow the diet, those things go away.

  • Don't want to give up coffee
    Val (Verified Purchase)

    Has anyone had luck adhering to the fruit in the morning but also having coffee? I lost weight in the 80’s by following it strictly, but can’t muster the motivation to give up my coffee. Other than that I love the diet. Any thoughts?

    • Val

      I wonder that too. I also wonder if I am losing weight due to the principles since I dry. It all day or if it is calorie reduction. Still fell good and do believe.

    • Anonymous

      Drink coffee on an empty stomach, wait about 45min. Then have fruit

  • Felt great, had more energy
    Wayne McClendon (Verified Purchase)

    To make a long story short,it works as advertised. In my younger years went from 180 to
    135 lbs in a few short months. Felt great, had more energy, and felt good about myself.

  • G'Nell De Lack

    How does fit for life diet affect diabetics?

    • Maribel (Editor)

      Hi G’Nell! Because of possible interactions with diabetes, please make sure to consult with your physician before taking this product.

    Edwin Rivera (Verified Purchase)


  • Irrelevant Comment

    I’m looking for the Diamonds website. Who knows the adress?

  • I lost about 70 lbs over 6 months
    Renee (Verified Purchase)

    I first read Fit for Life in 1990 after putting on 80 lbs with my pregnancy and breast feeding. I started having extreme heart burn no matter what I ate. My chiropractor boyfriend gave me this book to read. I started immediately and lost about 70 lbs over 6 months. I immediately had more energy and needed less sleep. My mood improved and I was always happy and energetic. I even started running. Over, the years, I did not follow the diet so well but when things got out of control I started back on it. It always immediately works and I feel great. I am 46 and very healthy. No medications or concerns. I do mostly eat organic and not a lot of meat. Medical evidence or not, this has worked for me for 18 years.

    • Your Name

      i am steeling your story

  • Can have water and fruit in morning?
    Mike McTamney (Verified Purchase)

    Can you drink water during the morning hours when you are eating only fruit? Not sure if this working – sorry for multiple questions that are the same.

    • Diane Marks

      I’ve had this book since the early 90’s, two years ago I started seriously and have lost 15kilos. I;ve never felt better in my life, so much energy–I even started jogging and I’m 59.But when you have your fruit in the morning I only have a cup of warm water with it, I have tried coffee or green tea but my stomach feels better with just the water,2 hours later I’ll have a green tea, I’m afraid cofee is now a thing of the past for me now, after being a good coffee drinker for years. I love the way I feel and I sleep so much better too.

  • Dr. Siegel is better than it.
    Judy Stark (Verified Purchase)

    I tried the Fit For Life Cookie Diet because it was cheaper than Dr. Siegel’s Cookie Diet. I loved the latter, but the former was cheaper and thought I’d give it a try. The Dr. Siegel’s cookies are wonderful. And you really felt like you were eating a cookie. And they worked just as stated. On the other hand, the Fit for Life cookies were pretty bad. I felt like I was eating flavored mud. I guess if you took really small bites and just swallowed instead of chewing, it might be okay. But, what’s the fun in that? I’m going back to Dr. Siegel’s Cookie Diet.

  • I not only lost weight, but I got healthy
    Lynne Dufour (Verified Purchase)

    I bought, read, and followed “Fit For Life”, back in the 80’s. It is funny to read, good and healthy to follow, and is true. I not only lost weight, but I got healthy. My mother followed it and her acid reflux went away. Both of us has energy and felt great. I am going to get back to the basics once again. I have to find my book.

    • Dave from California

      Fit For Life is the way to love your life!! My doctor was amazed at the complete turnaround of my health! Cholesterol, Blood Pressure is now normal. Sleep Apnea is now gone. 60 pounds of extra weight is also gone. Doctor told me to just keep doing what I’m doing. I wish I could convince all my friends to follow the recommendations in this book. It has given me my life back!!