Ask the Practitioner: How Do Popular Diets Stack Up Nutritionally?

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There are a lot of options and opinions on how to eat – but which one is healthiest and most nutritionally sound? Are there risks? If you peep the latest Instagram fitness influencer, you’ll find many people, products, foods, and philosophies focused on achieving a look at any cost, shifting health and long-term health to the wayside. Unfortunately, all too often there is a disconnect between health and fitness – what makes you fit isn’t always what contributes to a healthy lifestyle.

We asked WellnessFX practitioner, Registered and Licensed Dietician Lori Brizee to give us a break down of the various popular diets and help examine how they stack up nutritionally.

Lori Brizee is available for WellnessFX consults in Oregon.

8 Popular Diets: A Basic & Quick Rundown

1. Paleo Diet Basics

Eat only foods that our paleolithic ancestors ate: wild game, wild fish, nuts and seeds and their oils, berries, greens; some versions allow raw whole milk, cream and cheese. Most versions allow farmed meat and poultry but recommend that it is grass fed or free range.

Avoid: all grains, legumes and most starchy vegetables (i.e. potatoes); vegetable oils (i.e., corn, canola, safflower), low or nonfat and pasteurized dairy products, refined sugar (stevia is allowed), added salt, processed foods in general. Newer versions of the diet are more permissive, even allowing some non-gluten containing grains and starches such as potatoes.

2. Ketogenic Diet

Limit carbohydrates to 5% of total calories for first month, eventually up to 10% of your total daily calories. If you need 2000 calories/day, you do not want to eat more than 25 gm carbohydrates to start, and 50 gm carbohydrate long term. Urine is checked for ketones to be sure that a person is in ketosis (burning fat rather than carbohydrates for energy).

3. Atkins Diet

Avoid grains, legumes, fruits and eat high animal protein, high fat, high vegetable diet. This is similar to the ketogenic diet—in fact there is a “Modified Atkins diet for Seizures” that is a ketogenic form of the Atkins diet.

4. Zone Diet

30% protein, 30% fat and 40% carbohydrate. 3 meals + 2 snacks each with same proportions of protein, fat and carbohydrates. Protein comes from lean animal sources, carbs come mostly from vegetables and fruits, and fats from mono-unsaturated fats like almonds and olive oil.

Foods on the “unfavorable list” include fruits and vegetables high in sugars such as carrots, corn, raisins, and bananas as well as fatty red meats and egg yolks. Encourages avoidance of grains. You are supposed to eat within an hour of getting up, not let more than 5 hours go by without eating during the day and have a bedtime snack. Calories are limited to about 1200/day for women and 1500/day for men.

5. Lacto-Ovo Vegetarian Diet

Avoids all animal flesh, but allows eggs and dairy products.

6. Vegan Vegetarian Diet

Avoid ALL animal products.

7. Mediterranean Diet

Eat mostly plant foods including high amounts of vegetables and fruits, include mono-unsaturated oils (nuts, avocados, olive oil) daily, and limit red meat to a couple times/month; eat small amounts of poultry and fish regularly; get a significant amount of protein from beans and whole grains. Avoid processed foods, refined flour, and added sugar.

8. Dietary Approaches to Stop Hypertension (DASH diet)

Very similar to Mediterranean, high in vegetables and fruits, moderate in animal protein. Differs from Mediterranean in that it stresses addition of 3 servings/day of low and non-fat dairy products as these high calcium foods have been shown to help decrease blood pressure. Allows more animal protein than does the Mediterranean diet (still keeps meat intake low and focuses on poultry and fish).

Putting it All Together

Any diet which removes a complete food group (e.g. all grains and legumes in the paleo, Atkins and ketogenic diets) puts a person at risk for some nutrient deficiencies IF the diet is not well planned and recommended supplements added.

Some common deficiencies of nutrients among diets include:

Protein: Protein is one of the most important macronutrients consumed in our diet. It’s an important building block of bones, muscles, cartilage, skin, and blood. Your body uses protein to build and repair tissues, make enzymes, hormones, and other body chemicals.

Calcium: Essential mineral that maintains bones and nerves and muscle function
Iron: The tiny amount you need is crucial to normal body functions. If you do not have enough iron, your body cannot make hemoglobin, the oxygen-carrying component of red blood cells, and you may develop anemia, a disorder that occurs when there is not enough hemoglobin in the blood.

Zinc: Zinc is needed for normal growth, development, and sexual maturation, and helps regulate appetite, stress level, and sense of taste and smell. It also has antioxidant properties and plays an essential role in the immune system. Zinc can be found in Oysters, red meat, poultry, beans, nuts, whole grains, and dairy.

Vitamin C:  Vitamin C is needed by the body to form collagen in bones, cartilage, muscle, and blood vessels. Vitamin C also appears to improve absorption of iron or iron supplements taken orally. Because your body doesn’t produce vitamin C, you need to get it from your diet, as detailed by the Mayo Clinic.

Folic Acid: Folic acid/Folate is essential in the production of many cells, including red and white blood cells. Healthy folate levels support nerve function, bone and brain health, and help prevent serious birth defects of the spinal cord and brain.

Vitamin B12: Vitamin B12, or Cobalamin, is the largest and most complex vitamin currently known to man. It plays a key role in the normal functioning of the brain and nervous system. B12 can only be manufactured by bacteria and can only be found naturally in animal products. (with the exception of this animal product). Your body needs B12 to make red blood cells, nerves, and DNA.

Fiber: Good gut health is associated with adequate fiber and micronutrients, found in foods such as dry beans – think cooked soybeans, lentils, split peas and kidney, pinto, black, lima, garbanzo, navy and Great Northern bean – and vegetables and fruits, such as cooked spinach, artichokes, collard greens, broccoli, cauliflower, pears, raspberries and strawberries, brussels sprouts, asparagus, cabbage.

Saturated Fats: are solid at room temperature. Found in items such as coconut oil, milk, cheese, red meat, poultry, fish. The debates and research are ongoing; While the Dietary Guidelines for Americans recommend keeping your saturated fat limit to no more than 10 percent of your total calories (based on a 2,000-calorie-a-day diet, a 10 percent limit amounts to about 22 grams of saturated fat a day), the NCBI has also found that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD.

The table below gives information on specific nutrients that need special attention depending on the diet a person is choosing. Note: there are some balanced diets which meet ALL nutrient needs very well.

Table of diets and nutrients which need special attention:

Conclusion: “How do I know which one is for me?”

FAQ: “Is there a “diet” that is right for me?” My view is that when a person goes on any “diet”, they view it as a temporary step toward a long term goal.

If you truly want to improve your health, lose weight and keep it off, improve your sports performance, improve your blood levels of cholesterol and triglycerides, or lower your blood pressure, you need to find a lifestyle and eating style that you can follow for the rest of your life!

That doesn’t mean that you will never eat another cookie, bowl of ice cream or slice of bacon or salami; it does mean that you will follow your healthy lifestyle most of the time.

That being said, of the “diets” above, a Mediterranean or DASH style of eating have the most research behind them, and have been shown to improve heart health and can be helpful in weight loss, if accompanied by overall decreased caloric intake.

Limiting or even cutting out animal products can be very healthy, IF you plan well to make sure you are meeting all your nutrient needs. I am absolutely unimpressed with ketogenic, Paleo and Atkins styles of eating, as by limiting or avoiding whole grains and legumes, a person limits dietary fiber, which has been shown to be very important in building our gut microbiome, keeping our GI systems running smoothly, enhancing our immune system and lowering cholesterol.

These low carbohydrate diets also seem to result in SHORT TERM weight loss, with weight regain over 1-5 years. They are also very difficult to stick to long term.

About Lori Brizee, MS, RDN, LD, CDE

Location: Oregon
Practice & Philosophy:
My role is to be a facilitator to enable individuals to achieve their nutrition and lifestyle related goals. I use the latest scientific nutrition information as well as my clinical nutrition experience to guide my recommendations. I take time to learn about you as a person, how and what you are eating, medications and supplements you are taking, physical activity, sleep, and your long term goals. I then help you set short term eating and activity goals that you easily can achieve, and then build on over time to get to your long term goals. My recommendations cover eating style, specific foods to meet your individual nutritional needs, supplements (if indicated) and physical activity, sleep, and stress reduction.

Specialties include: Sleep, Energy and Fatigue, Heart Health, Metabolic Syndrome, Cholesterol and triglyceride levels, Joint and Bone Disease, Weight Management, Sports, Athletic Fitness, Pre-Diabetes and Diabetes (Blood Sugar Control), Women’s Health, Pediatric nutrition, and Special Health Care needs for all ages (including developmental disabilities, inborn errors of metabolism, cerebral palsy and associated feeding issues and other congenital conditions).

How WellnessFX Can Help

You can find more information about which diet is right for you by testing and tracking your biomarkers, examining markers like the ones mentioned above.

WellnessFX provides personalized advice from health professionals, via 1-on-1 consultations done over the phone. After you review your lab results as a WellnessFX member, you have access to our network of licensed health practitioners for an in-depth interpretation of your biomarkers. From women’s health to endurance training to weight loss, a consultation is an opportunity to leverage the data that’s now in your back pocket and identify potential health risks or areas of improvement.

The benefits of a consultation with any of our nutritionists, registered dietitians or physicians, are getting recommendations based on your unique biomarkers.

Consultations can be purchased as part of select bundled packages or on their own. If you’re not sure if you want one, you can always wait until you get your results to decide. Still overwhelmed? Don’t forget, we understand it can be hard to make changes, so our practitioners work with you to create realistic recommendations that fit your lifestyle.

To see all the bells and whistles that come with a WellnessFX consultation + tips on getting the most out of your consult, check out 5 Tips For Getting the Most Out of Your WellnessFX Consultation.

Regular blood screening is crucial for understanding your hormones, tracking progress, and measuring your associated risk, to hopefully stop a problem before it becomes a problem. Once you have the information, you can make educated, informed choices that fit your body’s specific and unique needs, from nutrition and lifestyle changes to hormone and risk monitoring.

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  • Karina Sanches Machado d’Almeida,1,2 Stefanny Ronchi Spillere,1,3 Priccila Zuchinali,1 and Gabriela Corrêa Souza;  Mediterranean Diet and Other Dietary Patterns in Primary Prevention of Heart Failure and Changes in Cardiac Function Markers: A Systematic Review; Nutrients. 2018 Jan; 10(1): 58. Published online 2018 Jan 10. doi:  10.3390/nu10010058 (Reviews Mediterranean, DASH, Paleolithic, and Vegetarian diets; shows improvement of heart failure with Mediterranean and DASH diets.
  • Scott JM, Deuster PA; Ketones and Human Performance. J Spec Oper Med. Summer 2017;17(2):112-116. (Reviews research on ketogenic diets for athletic performance. Few human studies have been done; they show equivocal or negative results of ketogenic diet on physical performance).
  • Gershuni VM, Yan SL, Medici V; Nutritional Ketosis for Weight Management and Reversal of Metabolic Syndrome. Curr Nutr Rep. 2018 Sep;7(3):97-106. doi: 10.1007/s13668-018-0235-0. (Shows positive effect of ketogenic diet for weight management, and reversal of metabolic syndrome).
  • Anton Stephen D, Hida Azumi, Heekin Kacey, Sowalski Kristen, Karabetian Christy, Mutchie Heather, Leeuwenburgh Christiaan, Manini Fodd M., Barnett Tracey E. Effects of popular diets without specific calorie targets on weight loss outcomes: Systemic review of findings from clinical trials.  Nutrients 2017, 9:822; doi:10.3390/nu9080822 Reviews Atkins (10 trials), DASH (1 short term trial), Glycemic-Index (2 short-term and 1 long-term trial), Mediterranean (1 short term and 2 long term), Ornish (2 short-term and long-term trials), Paleolithic (1 short and 1 long-term trial)and Zone diets (1 short-term and 2 long-term trials). All of the diets with the exception of the DASH diet produced some weight loss with long term weight loss anywhere from 1.8 to 10%.  Need to realize that there were no caloric limits for these diets. Any diet that reduces calories results in weight loss. The Atkins and Paleolithic and low carbohydrate diets reduced weight the most; in all of these diets caloric intake is reduced because of avoidance of major food groups. Most research that follows people very long term shows weight regain from any diet/weight loss program by 5 years (50% of people who have had bariatric surgery have regained some weight by 5 years).
  • Fred Brouns; Overweight and diabetes prevention: is a low-carbohydrate–high-fat diet recommendable?  European Journal of Nutrition (2018) 57:1301–1312 (Shows that any diet that reduces caloric intake reduces body weight and decreases risk of type 2 diabetes. A very low carbohydrate-high fat diet such as ketogenic is difficult to follow long term and there is lack of data supporting the long-term efficacy, safety and health benefits of low carbohydrate, high fat diets.  A balanced diet that provides 100-150 gm carbohydrate/day, along with lifestyle changes is safe and results in long-term prevention of type 2 diabetes.)
  • Davis Brenda and Melina, Vesanto; The New Becoming Vegetarian, The essential guide to a healthy vegetarian diet Healthy Living Publications, Summertown, Tennessee 2003. This is a very thorough book that reviews types of vegetarianism and how to create a healthy vegetarian diet.
  • Davis, Brenda and Melina, Vesanto; Becoming Vegan, The complete guide to adopting a healthy plant-based diet, Book Publishing Company, Summertown, Tennessee 2000 This is a thorough guide to how to have a healthy vegan diet and discusses nutrients of special concern.

The posts on this blog are for information only, and are not intended to substitute for a doctor-patient or other healthcare professional-patient relationship nor do they constitute medical or healthcare advice of any kind. Any information in these posts should not be acted upon without consideration of primary source material and professional input from one's own healthcare professionals.