Chapter Summary: Whole Food Plant-based Diet

Kristen Gialo DO, Neda Frayha MD

Within the field of Cardiology, primary prevention of heart disease is an area that is just MADE for primary care clinicians. What do the guidelines say, and how can PCPs best put them into action with our patients? Academic cardiologist Dr. Stan Liu is back for a helpful primer on the primary and secondary prevention of cardiovascular disease for the PCP.

Pearls:

• Stay up-to-date on nutrition information both to empower your patients and prevent the spread of misinformation.
• Stay up-to-date on nutrition information both to empower your patients and prevent the spread of misinformation.

Why is understanding whole food plant-based diet so important?

• Diet quality if the single leading predictor for premature death and chronic disease in the worldOnly
• 27% of medical schools in the US meet the minimum standards of nutrition education and that is only 25 hours
• One study found that 71% of participating interns felt they did not have sufficient nutrition training
• Primary care residencies only devote about 3 hours per year on nutrition, obesity and physical activity didactics
• Overall there is a lack of trusted resources available
  
  

How are we doing with our diets in the world?

• The average US diet is out-of-balance:
  • 63% calories come from processed foods
  • 25% calories are from animal products
  • 12% calories are from plant products (including juices and ketchup)
  • 6% calories are from vegetables, fruits, legumes, nuts, seeds and whole grains
• Based on WHO data:
  • Northern Europe, North America and Australia have the most  unhealthy diets with the least amount of low in fruits, vegetables, legumes, whole grains, nuts, seeds and other high fibrous foods
  • Rural Asia, South America and the Blue Zones have the healthiest diets

The Blue Zones?

• Areas of the world that are living healthier and longer lives
  • Okinawa, Japan
  • Sardinia, Italy
  • Nicoya, Costa Rica
  • Icaria, Greece
  • Loma Linda, California, United States
• Characteristics:
  • Strong sense of family
  • Socially engaged/connected
  • No smoking
  • Constant moderate physical activity
  • Eating plant-predominant diet that includes legumes
  •  

“Whole foods”:  foods you can visualize what has happened to them from coming start to finish

• Types of processing:
  • Level 1 - cutting, smashing, crushing, pulverizing (ie: apple that gets cut up) → 80% of calories should come from this category
  • Level 2 - moderate processing where it gets mixed with other stuff (ie: add crumble to smashed apple)
  • Level 3 - complex processing that often involves addition of chemicals not normally found in a person’s kitchen (ie: apple chips sold in a bag with added preservatives)
    • These may be foods that are designed by food scientists to make them more addictive by adding high fat/sugar/salt
    • Linked to increased risk of obesity, diabetes, cardiovascular disease

"Plant-based":

• Eat the rainbow everyday: diversifying color in your diet means diversifying micronutrients
• 95% of calories should come from vegetables, fruits, whole grains, legumes, seeds, nuts
• 5% of calories should come from fish, dairy and eggs

The data behind plant-based diets:

• Systematic review by Katz and Miller concluded a diet of minimally processed foods close to nature, predominantly plants is associated with health promotion and disease prevention
• Lancet 2019 review of 185 perspective studies showed that  people who consumed more dietary fiber had a lower risk of heart attack, death from heart disease, multiple types of cancers, stroke and diabetes
  • Not all carbohydrates are bad, the less refined the better
  • Complex carbs are a great source of fiber

Helping patients navigate eating plant-based diets:

• Screen for food insecurity and food deserts [> 1 mile (urban) or > 10 miles (rural) from a supermarket] and then connect them with local social services
• Whole foods diet does not have to be Whole Foods prices
  • Health staples can be affordable (oats, beans, rice)
  • Frozen and canned fruits and vegetables can be cheaper and healthy
  • There are lists available that provide low-cost options for eating a whole foods diet such as from the American College of Lifestyle Medicine (ACLM)

Making the transition:

• It can be hard to all of a sudden change to this type of diet so start with small goals and steps toward progress
• Some example goals if patients are having a hard time coming up with them:
  • One new plant-based diet per week
  • Start following one plant-based blog or author online
• Empower people to make it a fun thing and not a chore, something they can learn about and keep getting better at over time

References:

1. Adams KM, et al. Nutrition education in U.S. medical schools: latest update of a national survey. Acad Med. 2010;85(9):1537-1542. PMID: 20736683
2. Overview | American College of Lifestyle Medicine. American College of Lifestyle Medicine. https://lifestylemedicine.org/overview/
3. Antognoli EL, et al. Primary Care Resident Training for Obesity, Nutrition, and Physical Activity Counseling: A Mixed-Methods Study. Health Promot Pract. 2017;18(5):672-680. PMID: 27402722
4. Frantz DJ, et al. Cross-Sectional Study of U.S. Interns' Perceptions of Clinical Nutrition Education. JPEN J Parenter Enteral Nutr. 2016;40(4):529-535. PMID: 25712959
5. Hall KD, et al. Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake [published correction appears in Cell Metab. 2019 Jul 2;30(1):226] [published correction appears in Cell Metab. 2020 Oct 6;32(4):690]. Cell Metab. 2019;30(1):67-77.e3. PMID: 31105044
6. Fraser GE. Vegetarian diets: what do we know of their effects on common chronic diseases? [published correction appears in Am J Clin Nutr. 2009 Jul;90(1):248]. Am J Clin Nutr. 2009;89(5):1607S-1612S. PMID: 19321569
7. Frates B, et al. Lifestyle Medicine Handbook : An Introduction to the Power of Healthy Habits. Healthy Learning; 2021.
8. Karlsen MC, et al. Theoretical Food and Nutrient Composition of Whole-Food Plant-Based and Vegan Diets Compared to Current Dietary Recommendations. Nutrients. 2019;11(3):625. Published 2019 Mar 14. PMID: 30875784
9. Katz DL, Meller S. Can we say what diet is best for health?. Annu Rev Public Health. 2014;35:83-103. PMID: 24641555
10. Tuso PJ, et al. Nutritional update for physicians: plant-based diets. Perm J. 2013;17(2):61-66. PMID: 23704846
11. Willett WC, et al. Current evidence on healthy eating. Annu Rev Public Health. 2013;34:77-95. PMID: 23297654
12. USDA. DIETARY GUIDELINES for AMERICANS EIGHTH EDITION.; 2015. Accessed March 2, 2023. https://health.gov/sites/default/files/2019-09/2015-2020_Dietary_Guidelines.pdf
13. Mack B. Five Things You Can Do to Eat Healthier on a Tight Budget. American College of Lifestyle Medicine. Accessed March 3, 2023. https://lifestylemedicine.org/eat-healthy-on-a-budget/
14. EASY, HEALTHY, and LOW-COST MEALS for EVERY DAY of the WEEK. Accessed March 2, 2023. https://lifestylemedicine.org/wp-content/uploads/2022/07/Eating-on-Budget.pdf
15. USDA. Grains provided nearly a quarter of daily calories for the average American in 2009. www.ers.usda.gov. Accessed March 2, 2023.  https://www.ers.usda.gov/data-products/chart-gallery/gallery/chart-detail/?chartId=75130

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