5 Popular Diets Your Clients May Be On


Fashion trends come and go and diet fads also have their seasonality. You may find yourself working with an array of clients with special dietary requirements or practices which are ever changing.

Being familiar with some of these unique dietary approaches will provide you a better understanding of your client’s eating habits and also allow you to design a program catered specifically to their nutritional lifestyle.


It’s nearly impossible to be acquainted with every diet out there, from the baby food diet to the cabbage soup diet– the list is endless!

Don’t worry though, we narrowed it down to 5 of the most popular diets buzzing right now along with their description, recommended foods and/or those to avoid, as well as a consensus on each diet’s pros and cons!

1. Ayurveda

This holistic diet first hailed from India where its name translates to “the science of life”.  Ayurvedics believe the key to preventing disease is establishing a balance within the mind and body and becoming in tune with nature.

When following the Ayurvedic principles there are three different categories known as doshas, which reflect an individual’s body type and personality. Each dosha is based on the five elements of nature (space, fire, air, water, and earth):

Vata- represents air and may indicate erratic behavior and light-heartedness. Foods recommended are warm, cooked, nourishing and easily digestible foods. Avoid cool, non-digestible foods and sugar.

Pitta- represents fire and indicates a strong personality and leadership with intense emotions. Foods recommended are cool, raw, or lightly cooked foods. Avoid fried foods and spicy foods.

Kapha- represents water and is presented in a slow and steady demeanor with a strong foundation of loyalty. Foods recommended are light, warm and spicy foods. Avoid greasy foods and processed sugar.

Survey says this is an all-encompassing approach to health and relies heavily on bio-individuality and whole foods, however, there is little scientific evidence to back it up and could be limiting for some.

2. Ketogenic

This diet was first recognized in the 1920’s to help control epileptic seizures in those who did not respond to medication but has since been marketed as an aid in quick weight loss. Ketogenics is based on the process of ketosis, where the body uses ketones, a byproduct from fat metabolism, for fuel instead of carbohydrates.

This process puts the body in a fat-burning state. Ketosis typically occurs when the body goes into starvation mode, carbohydrate restriction or excessive exercise. Calorie intake must be limited and made up of 80% fat in order to reach this state of ketosis.

Recommended Foods:

  • Low-carb vegetables
  • Low-carb fruits
  • Meat
  • Poultry
  • Fish
  • Eggs
  • Dairy
  • Nuts and seeds
  • Healthy oils

Foods to Avoid:

  • High-carb vegetables
  • High-carb fruits
  • Grains
  • Beans
  • Sugar
  • Trans fats
  • Processed food

As controversy continues to swirl around this poular diet, there are several misconceptions that persist. Survey says studies have shown this diet can help individuals who suffer from epilepsy as well as support quick weight loss. Bear in mind, this diet can be hard to maintain for some individuals and has many side effects such as: dehydration, constipation, vomiting, high cholesterol, kidney stones, pancreatitis, excess fat in the blood, fatigue, behavior changes, bad breath and a metallic taste in the mouth.


This diet was designed for individuals who have difficulty digesting certain short-chain carbohydrates with common symptoms such as gas, constipation and bloating. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols which are all examples of different sorts of starches or short-chain carbohydrates that can cause stomach upset. Typically this diet is prescribed for those with IBS (Irritable Bowel Syndrome) to lessen symptoms.

High FODMAP foods to AVOID:

  • Artichokes, cauliflower, mushrooms, sugar snap peas
  • Apples, apricots, blackberries, boysenberries, dates, figs, guava, mangoes, nectarines, papaya, peaches, pears, plums, persimmons, prunes, watermelon
  • Dried and canned fruit
  • Gluten-containing grains
  • Beans
  • Lactose-containing dairy
  • Trans fats
  • Saturated fats
  • Sugar
  • Refined grains
  • Processed foods

Survey says this diet can be beneficial for those who suffer from IBS by alleviating symptoms and can improve an individual’s overall health habits due to the avoidance of sugar and processed foods. The only qualm is it may be difficult to maintain due to the long list of restricted common foods.

4. Paleo

Also known as the Primal diet, is centered around eating food similar to what our caveman ancestors ate in order to achieve optimal health. This means eating only whole foods which have not been processed or packaged.

Vigorous exercise is also incorporated into this diet theory, as well as only eating when hungry and getting plenty of Vitamin D. Paleo emphasizes high amounts of healthy fats and lower amounts of carbohydrates mainly coming from cooked or raw vegetables.

Recommended Foods:

  • Vegetables
  • Meat (organic, grass-fed)
  • Poultry (organic, grass-fed)
  • Fish (organic)
  • Eggs
  • Quinoa
  • Healthy fats
  • Fruits
  • Nuts

Foods to avoid:

  • Wheat, rye, barley, oats, brown rice
  • Dairy, except for ghee and grass-fed butter
  • Processed foods
  • Artificially low-fat foods
  • Sugars
  • Fruit juices

Survey says this incorporates a great deal of whole organic foods, high in fiber and healthy fat and discourages processed/high sodium foods. The pitfall here though is the price tag that comes with purchasing high quality meats. This diet may also be too low in carbohydrates for some individuals.

5. Vegan

This diet focuses on consuming plant-based foods and eliminates any animal or animal by-products. Basically, anything derived from an animal is restricted from the diet (i.e. butter, honey, yogurt, cheese). Vegans may also avoid cosmetics and soaps derived from animal products as well as products which have been tested on animals.

Recommended Foods:

  • Vegetables
  • Fruits
  • Grains
  • Beans
  • Nuts and seeds
  • Oils

Foods to avoid:

  • All animal products

Survey says this can support weight loss, reduce risk for heart disease and support the environment. For some though, a strict plant-based diet could lead to anemia as well as other nutritional deficiencies (individuals going vegan should be knowledgeable about how to replace vitamins and minerals such as B12 which is a vitamin more readily absorbed in the body from animal protein).

Check out these other forms of vegetarianism:

Lacto-ovo vegetarian: someone who eats vegetables, eggs, and dairy products but who does not eat meat
Lacto-vegetarian: someone who does not eat meat and eggs, but who eats dairy products
Pescaterian: vegetarian who consumes fish
Pesco-pollo vegetarian: vegetarian who consumes fish and chicken
Flexitarian: a more flexible version of the vegetarian diet; meat is eaten occasionally but is primarily plant-based

As always, there is no one size fits all approach when it comes to wellness. Different dietary approaches work for different people, well others may not. This is why it is important to keep an open-mind when working with a diverse group of clients by respecting their values both on and off their plate!

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Institute of Integrative Nutrition’s Alumni Dietary Theory Library: https://courses.iin.edlumina.com/courses/159


Regina Pellegrino

Regina Pellegrino is a certified Health Coach through The Institute for Integrative Nutrition, as well as a certified Fitness Specialist through San Diego Mesa College. She is currently working towards her accreditation as a Registered Dietitian Nutritionist. Her goal is to spread her thirst for knowledge and passion for living a healthy lifestyle by helping others achieve their optimal health. Learn more about Regina at http://reginapellegrinodieteticportfolio.weebly.com


Guest authors offer experience and educational insights based on their specific area of expertise. These authors are contributing writers for the NFPT blog because they have valuable information to share with NFPT-CPTs and the fitness community at-large. If you are interested in contributing to the NFPT blog as a guest, please send us a note expressing your interest and tell us how you can contribute valuable insights to our readers. We look forward to hearing from you! Send to [email protected]
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