“There are as many ‘right’ diets as there are people on the planet” is HCI’s 1st Dietary Paradigm and there’s good reason why.  

It is so important to “get” this as Health Coaches because it encourages us to treat each person as a unique individual with his/her own dietary needs, which is exactly the reason why we created a ground-breaking formula to help you learn 100 Dietary Theories in 10 Minutes—our all-time most popular lesson handout!

Seeing as we just bid farewell to National Nutrition Month created by the Academy of Nutrition and Dietetics to promote nutrition education annually in the month of March, we decided to give you a little overview or crash course of the types of diets that exist in today’s modern world. Welcome to Diets: 101!

But first let’s take a look at the origin of the word “Diet”. A lot of people have negative associations with it because it not only contains the word “die,” but in today’s society we have gone to great lengths to butcher the original meaning of the word by creating all kinds of fad diets in a weight-loss market nearing $70 billion this year in the US alone according to MarketResearch.com.

Here’s the etymology of the word “diet” from the Merriam-Webster dictionary:

Origin and Etymology of diet

Middle English diete, from Anglo-French, from Latin diaeta, from Greek diaita, literally, manner of living, from diaitasthai to lead one’s life
The word diet first appeared in English in the 13th century. Its original meaning was the same as in modern English, “habitually taken food and drink.” But diet was used in another sense too in the Middle and early modern English periods to mean “way of living.” This is, in fact, the original meaning of diet’s Greek ancestor diaita, which is derived from the verb diaitasthan,meaning “to lead one’s life.” In Greek, diaita, had already come to be used more specifically for a way of living prescribed by a physician, a diet, or other regimen.

Isn’t it telling that the word “diet” in today’s weight-loss obsessed world has far less of a focus on a long-term way of living than on a short-term crash diet? How far we have strayed from diet’s original meaning. Luckily, at HCI, we know that dieting doesn’t work and we strongly believe however that every person can and will (with the right support from a Health Coach) find a diet, or way of life, that works for them. So what follows is an overview of diets today (at least the 100 that we cover in Become a Health Coach), which you’ll notice are as varied as the people who follow them.

Current Diet Crazes That Are All The Rage

As Health Coaches you are probably well aware of whatever the latest diet fad is since your clients probably come to you touting its benefits and wanting to try it on thmselves. The Paleo Diet and Ketogenic (Keto) Diet are all the rage right now. The former advocates for carnivorous consumption that dates back to Paleolithic times, basically a lotta meat and no grains, whereas the Keto Diet (originally created to treat epileptic fits) opts for a diet really high in good fats and no carbs in the form of grains and breads to force the body into a ketosis state where it’s burning fat as a fuel source instead of burning carbs as a fuel source.

Another diet that originated to treat Celiac Disease in which the person cannot tolerate any amount of gluten is the latest Gluten-Free craze that is sweeping across America, and other parts of the world. This diet poses that you can get rid of all kinds of unpleasant digestive issues such as bloating, diarrhea, flatulence etc by eliminating foods that contain gluten such as: wheat, rye, barley, and a host of store-bought, preserved foods that contain gluten such as condiments, deli meats and canned soups.

Diet Companies That Have Stood The Test of Time

Then there are those diets from fitness and diet gurus that are as old as your grandma like The Jane Fonda Diet. If you came of age in the seventies or eighties you’ll have most certainly heard all about Weight Watchers that sprouted in 1963, which spread to 30 countries and has a net worth of well over $200 million—in which Oprah has a big stake.

Another biggie from the era that popularized low-fat foods is Slim Fast, which sprouted in 1977 and is headquartered in Palm Beach Gardens, Florida. Together with Weight Watchers, these two mega diet companies were the start of companies selling pre-made diet ‘food’ in the form of bars, shakes, pre-packaged meals etc to “make it easy” for the consumer to count the calories. And let’s not forget the ubiquitous Jenny Craig Diet, which began in 1983 in Australia and today has millions of followers.  

Ancient Diets That Are Ways Of Life Still Today

On the complete opposite end of the corporate diet scale are ancient diets such as the Ayurvedic Diet, an ancient way of life dating back thousands of years that originated in India. Ayur means “life” and Veda means “knowledge”. Ayurveda is a philosophy of eating and living with the underlying theory that health is created when there is a balance between the three bio-elements in the body aka Doshas: Vata (space and air), Pitta (fire and water), and Kapha (water and earth).

Another ancient diet is the Kosher diet that many Jews around the world still follow religiously today, which originates from Biblical times, in which Jews eat only meat from animals that chew their cud and have split hooves such as cows and goats and do not mix meat and milk (cheeseburgers and meat lasagne) since it’s written three times in the Torah not to cook a baby goat in its mother’s milk. To be deemed Kosher, animals must be slaughtered by a trained ‘shochet’ trained in kosher slaughtering.

Fad Diets That Have Already Faded

Then there are diets that either seem to fade as fast as they pop up or have actually been blacklisted by critics such as Dr. D Adamo’s popularized and highly criticized Blood Type Diet based on eating completely differently according to whether you have an O, A, B or AB blood type, which many people don’t even know. But Adamo went on to create version two of his diet called The Genotype Diet in which he claims you can actually change your genetic destiny by eating differently according to whether you are a hunter, gatherer, teacher, explorer, warrior, or nomad genotype.

There’s also the Aztec Diet based on the ancient way that people ate in the Aztec Empire in Mexico, which thrived between  1345 and 1521 CE. This fad diet was started by Dr Bob Arnot, a New York Times Bestselling author, even though there is little content on the net about it, who who seems to have a fetish when it comes to chia seeds since the diet is based on consuming large amounts of this ancient grain so much so that it begins with consuming three chia smoothies per day for three days o start. Or the bogus 3-Day Diet aka The Military Diet in which you follow a strict 3-day eating regimen that recommends half a grapefruit and a slice of toast with a dollop of peanut butter for breakfast, tuna on a slice of toast for lunch and a dinner of 3 ounces of any meat followed by a cup of vanilla ice cream.

Regional Diets That Are Popularized Globally Today

There are regional diets that have been around for as long as people have resided in those regions such as the Mediterranean Diet based on the Mediterranean way of eating: lots of veggies, healthy fats, whole grains, olive oil, etc that are popular today in America where Mediterranean food is available for the most part. Variations of this diet have since taken off such as the MediterrAsian diet started by a woman called Trudy with a passion for Mediterranean food and her partner, Ric, with a passion for Asian food who combined their love of food with their love for one another and created the MedierrAsian Way.

There are other regional diets by advocates like National Geographic explorer and author, Dan Buettner, who went on a quest to locate regions around the world in which the highest number of centenarians reside and found that the top five locations were: Ikaria, Greece: Okinawa, Japan; Sardinia, Italy; Loma Linda, California; and Nicoya Peninsula, Costa Rica. He titled his books containing his research: “The Blue Zones: Lessons for Living Longer From The People Who’ve Lived The Longest” and “The Blue Zones Solution: Eating And Living Like The World’s Healthiest People”. 

Diets To Prevent, Reverse & Treat Diseases

Then there are diets were born from the attempt to treat and prevent serious diseases with food such as the Migraine Diet, which advocates an extensive list of potential migraine inducing foods such as cured meats, aged cheeses, citrus fruits, anything containing MSG, nitrites and sulfites. The IBS Diet to treat Irritable Bowel Syndrome, which claims that certain carbs make IBS symptoms worse and these carbs form the acronym FODMAPS: Fermentable, Oligo-saccharides, Di-saccharides, Mono-saccharides and Polyols. The Low Glycemic Index Diet advocates for eating foods that don’t elevate your glycemic index, in other words don’t spike your blood sugar or increase your glucose levels. This diet states eating a lot of non-starchy veggies, ancient whole-grain, stone-ground grains, fermented dairy, healthy fats like avocado and olive oil etc and to stay away from processed foods that contain tons of added sugar. And then there are other doctor endorsed diets such as The Prediabetes Diet meant to prevent the onset of Diabetes and the Hormone Cure Diet created by Dr Sarah Gottfried aimed primarily at women to help stabilize hormones using food and supplements. All of which have the intention to heal disease through dietary changes.

Variety of Vegetarianisms in Vogue

There are diets that cut out red meat, poultry, and fish—all various forms of vegetarianism—such as Lacto-Vegetarian (eats dairy), Lacto-ovo Vegetarian (eats dairy and eggs), Vegan (no dairy, no eggs, no honey in strict cases) and Raw Foodist (eats only raw food and nothing cooked.) And there’s Pescetarians who eat mostly vegetarian but include fish and the new Flexitarians made famous by registered dietician nutritionist, Dawn Jackson Blatner, who is part of a Flexitarian movement that apparently 22 million Americans now follow in which Flexis have been labeled “part-time vegetarians” meaning they eat mostly vegetarian but don’t mind the occasional steak or burger and they abstain from meat consumption mostly for the sake of saving the planet and its animals. The impetus behind the Flexitarian movement apparenlty began with the publication of a book in 1971 by Frances Moore Lappé titled “Diet For A Small Planet” explaining why meat diets are harmful to the environment.

Anti-Diet Diet Gurus

There are diets that you may never have heard of that have massive followings so much so that their creators are nothing short of diet gurus like celebrity weight-loss guru, John Gabriel, who ironically is anti-dieting. He created The Gabriel Method (note that it omits the word “diet” in the name) after he supposedly lost over 220 pounds without dieting or surgery and now has a body fit for the Milan runway. His program is based on coming to understand the reasons why you are holding onto your fat and using the power of visualizations and transforming your limiting and negative beliefs to shed the pounds. He knew his weight loss was not about calories and made it his life’s mission to help others lose weight easily by letting go fo their issues that caused them to hold onto their weight in the first place. His book has been translated into 16 languages in 60 countries around the world. Gabriel believes wholeheartedly that when your body becomes your ally, and not your enemy, you will lose weight naturally and he certainly is the ideal poster child for his mission.     

Catchy Popular Diets You May Never Have Even Heard Of

You’ve probably never heard of some diets with names like the P.I.N.K Method (an acronym for Power, Intensity, Nutrition, Kardio with a “k”) started by Cynthia Pasquella-Garcia who was once suicidal and overweight and turned her life around by studying nutrition and founding the Institute for Transformational Nutrition and is now a rich and famous celebrity nutrition expert. The diet is supplemented by supplements, cook books and DVD workout videos. Or the Engine 2 Diet started by Rip Esselstyn, a former firefighter and triathlete turned food activist who advocates for his trademarked “plant-strong” diet. He wrote two books: “Engine 2 Diet” and “Plant-Strong”—which was first published under the title, “My Beef With Meat”. Esselstyn originally turned a Texas, meat eating firefighters station into a “plant-based powerhouse” and now has over 15,000 people who have joined his plant-strong food and lifestyle challenge.

Diet Crazes That Are Taking Over The Planet

On the other hand there are some diets that you you’ve heard so much about that you couldn’t get away from if you tried such as Silicon Valley investor and tech entrepreneur, Dave Asprey’s, Bulletproof Diet. Asprey partitions his diet into easy-to-follow colors like a traffic light: Green Zone (eat as much as you want); Orange Zone (go easy on these) and Red Zone (avoid at all costs.) To go with his diet, Asprey also patented his Bulletproof coffee that contains Bulletproof-branded coffee beans that he claims are mould-free unlike commercial beans, grass-fed butter and a brain elixir called Brain Octane comprised of C8 MCT’s, which metabolize more efficiently into ketone energy than other oils. Asprey claims it is 18 times more potent than coconut oil. BTW tibetans have been drinking a strong tea brew with yak butter since the Tang Dynasty in the 7th century!

Clean Diets Versus Dirty Diets

Then there are diets that have become environmental and anti-corporate movements such as the Clean Diet, which started as a backlash against the corporate food industry controlling our food consumption. Health nut junkies around the world jumped on board swearing by healthy, clean food that is not commercially produced, and is hormone, antibiotic, preservative and additives, and flavorings free etc. No one really knows who started it or when it started exactly and there’s a lot of contention around this movement in the foodie world. Some critics have slated the movement for labeling foods clean as it means that other foods must be ‘dirty’. Some would even say that at the extreme end of the clean eating movement is an eating disorder called Orthorexia, a term coined in 1998, which refers to people who eat only uber health, “pure” food to the extent that it takes over their lives. The irony is that these foods are actually healthy in contrast to corporate factory-made ‘food’, they’re the foods that our grandmothers once prepared.

Food Fanatics & Detox Diets

There are diet fanatics out there who swear by dietary extremes such as Fruitarianism in which you subsist purely on fruit; or Raw Food Diets in which you eat only raw food or Juicing in which you juice all your veggies. Some of these diets are ways of life and some are short lived detox liquid diets or cleanses. The extreme detox version is a diet that has stood the test of time called the Master Cleanse in which you drink a concoction of lemon, cayenne pepper and maple syrup while eating nothing else for ten days straight. It’s also known as the Lemonade Diet and was started in 1941 by Stanley Burroughs. Also critics have said that this diet doesn’t work and that it’s dangerous to drink only lemonade and nothing else for that many days due to the lack of rounded nutrition, thousands still swear by it. Then again there are even the select few who have sworn off food for the rest of their lives and claim to subsist solely on air. 

Diets That Question Our Bodies’ Wisdom

The Acid-Alkaline Diet claims that for optimum health you need to balance the PH levels in your urine based on the acid or alkaline content of foods. Many doctors have claimed this theory to be a myth although the diet has many loyal followers. Apparently the idea was formed in the 19th Century by French biologist, Claude Bernard, who realized that if he changed rabbits’ diets from plant-eating to meat-eating, it made their urine more acidic and less alkaline. Scientists jumped on board and ran with it and so did celebrities and now it’s a major diet craze. Critics of this diet like Dr Axe believe it to be total nonsense and have published pieces on why this theory is pure myth. 

Similarly, Food Combining, a way of eating seized by the rich and famous such as Fergie and Helen Mirren was started by Kathryn Marsden whose two bestselling books on the subject have been slated by nutrition experts as total hogwash. The diet claims that you should never eat carbs and proteins at the same time as each needs to go through its own digestive processes. Also, it claims that you should only eat fruit twenty minutes before a meal otherwise it will ferment in your intestines. Critics say this isn’t true and that your body knows what to do. However, Marsden, a hotel manager turned diet guru, swears that Food Combining saved her husband’s life after he was diagnosed with stomach cancer in 1984 and subsequently followed her food combining regimen.

Diets That Save Lives

Finally, there are redeeming diets that began from deep love such as a mother’s desire to save her child’s life. One such diet is The Specific Carbohydrate Diet (SCD), which was started by a stay-at-home mother, Elaine Gottschall, whose four-year-old daughter was diagnosed with Ulcerative Colitis and not one doctor in all of New York who Elaine visited recommended that she change her daughter’s diet to cure the disease. Instead their only recommendations was an operation to remove her daughter’s colon and attach an external bag to collect her body’s waste for the rest of her life. A chance introduction to Dr Sidney Valentine Haas was Elaine’s final hope. Finally, she was told to radically alter her daughter’s diet by eliminating certain carbs and within ten days she noticed changes and within two years her daughter’s symptoms were gone. She saved her life, went on to study biochemistry, published a book titled “Breaking the Vicious Cycle” and helped to heal thousands of people using The Specific Carbohydrate Diet! 

Know of a diet that we haven’t mentioned here that you want to tell us about? Share it in the comments below. Or let us know if you follow a particular diet or way of eating that works best for your body type and constitution. 

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