What is the healthiest diet? What is the best way to eat so that you can feel great, have more energy, get sick less often and live longer?
What you eat has a significant impact on your health and well being. You have the responsibility of choosing what you and your family will eat. You have the chance to either improve your health and prevent disease or harm your health and develop disease.
One of the best places to discover the healthiest way to eat is the Blue Zones. Blue Zones are regions of the world where people consistently live long healthy, active lives. There are high rates of centenarians in the five Blue Zones. The people in these regions generally don’t take medication or suffer disease.
There are five Blue Zone regions:
- Okinawa, Japan
- Loma Linda, California
- Sardinia, Italy
- Nicola Peninsula, Costa Rica
- Ikaria, Greece
Researchers went into these regions to find out why these people live so long. They found each region had a number of lifestyle practices in common (no smoking, importance of family, gardening, constant moderate physical activity). When it came to diet they also have a number of things in common. Every one of the five regions eats a plant based diet. I’ve listed below some of the details (Buettner 2012).
Blue Zones diet:
- Plant based diet
- Very little meat (a few times a month)
- Legumes every day (1 cup on average)
- Very little processed/refined/fried foods.
- Eat from the garden
- At least 2 vegetables at each meal
- Whole grains (e.g. corn tortillas, semolina flatbread)
- Most calories from carbohydrates (50-80%)
Health habits to reduce risk of disease
Another place to discover the healthiest way of eating is the EPIC-Potsdam Study (Ford et al 2009). In this study, researchers wanted to find out how four healthy habits affect the risk of chronic disease. The researchers looked at 23,000 people in Germany aged 35-65.
The four healthy habits they looked at were:
- Healthy diet: high intake of fruits, vegetables and whole grain bread and low meat consumption
- Never smoking
- BMI (body mass index) below 30
- Exercise at least 3.5 hours a week
Reducing risk of disease
The study found that people who followed all four of these health habits significantly reduced their risk of disease compared with participants with none of the healthy factors. This following all four habits had:
- 78% lower risk of developing chronic disease
- 81% lower risk of heart attack
- 50% lower risk of stroke
- 36% lower risk of stroke
This study shows that the potential for preventing obesity and chronic disease through healthy living is enormous. It also shows that a high intake of fruits, vegetables and whole grain bread and low meat consumption is health promoting and disease preventing.
Two more studies that shed light on the healthiest diet is the EPIC-Oxford Study (Davey et al 2002), including 65,429 people and the Adventist Healthy Study-2, including 96 469 people. The EPIC-Oxford study is one of the biggest studies of non-meat eaters in the world.
These two studies compared the eating patterns of meat eaters, semi-vegetarians, pescovegetarians, lacto-ovo vegetarians and vegans and how their eating patterns impacted on weight, disease and mortality.
Both studies showed that those on a plant-based diet, on average, have a lower BMI than meat eaters. Vegans consistently weigh less than vegetarians, fish eaters, and meat eaters. In the Adventist Health Study-2, vegans were the only cohort to be under the recommended BMI of 25 (Tonsdad 2009).
Reversing heart disease
The healthiest way to eat should reverse or treat chronic disease. But is this even possible?
In 1990 Dr Dean Ornish published a landmark study showing that coronary heart disease could be reversed with comprehensive lifestyle changes. He assigned 28 patients to an experimental group who went on a low-fat vegetarian diet, stopped smoking, had stress management training and did light exercise. He compared these patients to 20 patients in a usual-care control group. After 1 year, 82% of the experimental group had an average disease regression. And this was without the use of lipid-lowering drugs.
Dr Ornish’s research showed that not only can you slow and stop heart disease, but it can actually be reversed. The blocked arteries in people’s heart were opening up and becoming unblocked.
A plant-based diet is the only diet that has shown to be able to reverse heart disease.
A plant-based diet is the healthiest diet
When you look at all the evidence you can see that a plant-based diet is the healthiest way to eat. It reduces your risk of disease, reverses disease, increases longevity, and helps you to lose weight or maintain your weight.
The World Health Organisation recommends a plant based diet. They don’t specifically recommend meat or other animal products. These are their recommendations for a healthy diet for adults:
- Eat plenty of fruits, vegetables, legumes, nuts and whole grains
- Eat at least 400g (5 serves) of fruits and vegetables a day
- Less than 10% of total energy intake from free sugars
- Eat less than 30% of total energy intake from fats (avoid saturated fat, don’t eat trans fats)
- Less than 5 g of salt (approximately 1 teaspoon) per day
Why are plant-based foods so healthy?
Whole plant foods are nutrient dense. They are full of health-promoting nutrients:
- An ample amount of plant protein
- Resistant starch
Plant foods contain all of these benefits while being low in the things that are harmful to your body. Plant foods contain:
- No cholesterol
- No trans fats
- Very little saturated fat
- Very little total fat
Are carbohydrates healthy?
Most plant foods are primarily made up of carbohydrates. The chart below shows you the percentage of calories from carbohydrates in whole plant foods. As you can see, plant foods are mostly made up of carbohydrates. Even non-starchy vegetables such as broccoli, cucumber and celery are mostly carbohydrate.
Carbohydrates in plant foods
|Carbohydrates as a percentage of calories|
We need carbohydrates for good gut health
Our gut bacteria feed on the fibre found in carbohydrates. Dietary fibre is found only in plant foods. Low carbohydrate diets tend to result in reduced intake of fibre and fruits and increased intake of protein from animal sources, cholesterol and saturated fat (Noto et al 2013 ).
Whole grains are healthy
You have probably heard people say that grains are bad for you, particularly wheat. But research consistently shows that whole grains are health promoting.
Whole grains reduce risk of disease
In 2016, the journal Circulation (Zong et al) published research that analysed 14 different studies involving 786,076 participants. The study looked at whole grain consumption and all-cause mortality. The results showed that people who ate 70 grams/day of whole grains, compared with those who ate little or no whole grains, had:
- 22% lower risk of total mortality
- 23% lower risk of cardiovascular disease mortality
- 20% lower risk of cancer mortality
The researchers recommended eating at least 3 servings each day of whole grains to improve long-term health and prevent premature death.
Whole grains including wheat reduce weight gain
A review published in the Journal of Nutrition in 2012 (Ye et al) researchers compared people who rarely or never ate whole grains compared to those who at 3-5 serves of wholegrain, including wheat, per day. The results showed that those consuming grain had:
- a 26% reduction in the risk of type-2 diabetes
- a 21% reduction in the risk of heart disease
- consistently less weight gain
Low carbohydrate diets increase risk of disease
In 2013 PLOS One journal (Noto et al) published an article looking at low carbohydrate diets and all-cause mortality. The article analysed 17 different studies involving 272,216 people. Researchers found that low-carbohydrate diets were associated with a significantly higher risk of all-cause mortality.
Avoid refined carbohydrates
The only type of carbohydrates that we should be avoiding is refined carbohydrates. Refining carbohydrates remove all of the good stuff. When carbs get refined you lose (Davis 2016):
- 80-90% of fibre
- 70-80% of vitamins and minerals
- 95% of the phytochemicals
Vegetables & fruit
Vegetables and fruit are high in nutrients and low in calories. They are the lowest energy dense food there is, helping you to fill up on nutrient-dense food without taking in excess calories.
In a study published in 2006 (Ledikwe et al), researchers looked at the food intake of 7356 men and women. The researchers analysed the energy density of their food, their energy intake and their body weight. They found that the people with a high fruit and vegetable intake had the lowest energy density values and the lowest obesity prevalence.
How much fruit and vegetables do Australians eat?
Australians aren’t eating enough fruit and vegetables. (ABS 2013)
- 50.2% of Australians don’t eat 2 or more serves of fruit per day
- 93% of Australians don’t eat 5 or more serves of vegetables per day
- 5.1% of Australians DO eat the recommended serves of fruit and vegetables per day
What about protein?
Whole plant foods contain all the essential nutrients (with the exception of vitamin B12 and vitamin D) in proportions that are ideal for your body. You don’t need to eat meat to get enough protein. We only need 10-15% of our calories to come from protein. Research shows that most vegans get more than this amount of protein in their diet (Rizzo et al 2013).
The American Heart Association states that “You don’t need to eat foods from animals to have enough protein in your diet. Plant proteins alone can provide enough of the essential and non-essential amino acids, as long as sources of dietary protein are varied and caloric intake is high enough to meet energy needs.”
The chart below shows you the protein content of plant foods as a percentage of calories. You can see that plant foods easily contain an ample amount (10-15% of calories) of the recommended intakes (Davis 2016).
Protein in plant foods
|Protein in plant foods as a percentage of calories|
A plant based diet is the healthiest diet
If you want to live longer and reduce your risk of disease, then switch to a plant-based diet. If you want to give your kids the best start in life then include mostly whole plant foods in your meals.
What do you eat on a plant based diet?
- Brenda Davis RD – Eating for life… Designing an Optimal Diet January 2016
- Buettner, Dan. The Blue Zones: 9 Lessons for Living Longer from the People Who’ve Lived the Longest. 2012.
- Ford et al. Healthy Living Is the Best Revenge. Findings From the European Prospective Investigation Into Cancer and Nutrition–Potsdam Study. Arch Intern Med. 2009;169(15):1355-1362
- Davey et al 2002. EPIC–Oxford: lifestyle characteristics and nutrient intakes in a cohort of 33 883 meat-eaters and 31 546 non-meat-eaters in the UK. Public Health Nutrition: 6(3), 259–268.
- Australian Bureau of Statistics. 2013.
- Zong, G. et al. Whole Grain Intake and Mortality from All Causes, Cardiovascular Disease, and Cancer: A Meta-Analysis of Prospective Cohort Studies. Circulation. 2016 Jun 14; 133(24): 2370–2380.
- Noto, H et al (2013) PLOS One. Low-Carbohydrate Diets and All-Cause Mortality: A Systematic Review and Meta-Analysis of Observational Studies.
- Tonstad S, Butler TL, Yan R, Fraser GE. Type of vegetarian diet, body weight, and prevalence of type 2 diabetes. Diabetes Care 2009;32:791–6.
- D. Ornish, Brown SE, Scherwitz LW, Billings JH, Armstrong WT, Ports TA, McLanahan SM, Kirkeeide RL, Brand RJ, Gould KL. Can lifestyle changes reverse coronary heart disease? The Lifestyle Heart Trial. Lancet. 1990 Jul 21;336(8708):129-33.
- E. Q. Ye et al., “Greater Whole-Grain Intake Is Associated with Lower Risk of Type 2 Diabetes, Cardiovasular disease, and Weight Gain,” Journal of Nutrition 142/7 (July 2012): 1304-13
- Rizzo, N., Jaceldo-Siegl, K., Sabate, J., & Fraser, G. (n.d.). Nutrient Profiles of Vegetarian and Nonvegetarian Dietary Patterns. Journal of the Academy of Nutrition and Dietetics, 1610—1619.
- Vegetarian Diets. The American Heart Association.
- J H Ledikwe, B J Rolls, H Smiciklas-Wright, D C Mitchell, J D Ard, C Champagne, N Karanja, P H Lin, V J Stevens, L J Appel. Reductions in dietary energy density are associated with weight loss in overweight and obese participants in the PREMIER trial. Am J Clin Nutr. 2007 May;85(5):1212-21.