What Does Eating Plants Do For Weight Loss? Part One

Why is being overweight becoming the new norm?

It cannot have escaped your attention that people in general are getting larger. Statistics Canada reported in 2014 that 54% of our population over the age of eighteen are overweight or obese (1). Forbes reports that 61% of Canadians have a BMI of at least 25 (2). (BMI or Body Mass Index is a simple calculation using a person’s height and weight. A BMI of 25 to 29.9 is considered overweight; a BMI of 30 and over is considered obese.) Children are not escaping this problem either. Obesity rates between 1989 and 2004 increased from 2% to 14% for boys and from 2% to 11% in girls (3). Our neighbours to the south are faring even worse. A 2015 US study found 40% of men and 30% of women to be overweight and 35% of men and 37% of women to be obese (4). This means that an astounding 75% of US men and 67% of US women are either overweight or obese. We should not find this all that surprising. The diet we consume here in the Western world is high in fat, protein and refined carbohydrates. In truth it is not possible to eat all you would like of a Western diet and maintain a healthy weight.

There are numerous ways to lose weight. Many leave you hungry and unsatisfied. Some push fanatical exercise. Others advocate unhealthy food choices. Wouldn’t it be wonderful to eat until you are satisfied yet not gain weight? To never have to force yourself to push away from the table? To eat nutritious foods that make you flourish? To simply enjoy an invigorating walk instead of spending hours at a gym or compelling your body to run the roads? It turns out that this is not an impossible dream. You need only eat the right types of food.

Plant-based diets have been found to be highly effective for weight loss. Such weight loss occurs at the healthy rate of about 1 pound per week and doesn’t require excessive exercise. Plant-based diets result in more calories being burned after meals (thermic effect of food) and fewer calories being stored as fat compared to diets containing animal foods (possibly because animal protein results in much higher insulin release than does plant protein) (5). Eating plant-based even results in an 11% higher resting metabolic rate (13). There is no need to be concerned that plant-based diets are deficient in some nutrients. They contain more fiber, vitamins A, C, and E, thiamin, riboflavin, folate, antioxidants, phytonutrients, calcium, magnesium, and iron than diets containing animal foods (6). Only vitamin B12 is of concern and it is easily supplemented (see “The B12 Conundrum”).

Though the required alterations in eating habits are simple, the transformation is not necessarily easy.
People become quite attached to their favourite foods and will not give them up without good reason, especially if they feel they will never be allowed to eat them again. Many people go so far as to say that they would rather die than change their diet. This is a legitimate “gut” reaction. However, in actuality these fears are unfounded. All of the tastes enjoyed on the Western diet can continue to be relished on a whole-food plant-based diet. And if you want to indulge in your old favourite dishes once in a while, who’s to stop you? In the end you’ll find that you won’t miss the foods you no longer eat. Your taste buds change and soon, believe it or not, so will the foods you most desire. Hopefully in the following paragraphs I can give you enough good reasons to successfully make the transition to a completely plant-based lifestyle.

Why is our body weight more difficult to control than that of our ancestors?

What is actually causing the increase in body weight in our population? Let’s look at the statistics. In the US, food consumption studies are clear. Between 1970 and 2010, US citizens added 500 extra calories to their diet every day, half of which come from fats and oils and half from refined carbohydrates. Fat intake has increased by 67%. Though consumption of beef has fallen, that of chicken has more than doubled and cheese consumption has tripled. Sugar intake has remained fairly stable but corn sweetener has tripled. (7,8). Canadian statistics are not as detailed but they do offer some insight into the deplorable state of our diets. Only 40% of Canadians are consuming even five servings of fruits and vegetables a day. The recommendation for adults is to eat at least 7 to 10 servings of fruits and vegetables daily….and even this is on the low side for health. Fat intake of Canadians has decreased slightly from that of 1970 but remains very high, between 31% and 35% of daily calorie intake. Considering that the consumption of processed foods has soared and the nutrient content of processed foods is difficult to be accurately included in a food questionnaire, it is likely that the fat intake in Canada has actually increased right along with that of the US (9). Refined sugar intake has decreased but this is more than compensated for by the increase in high fructose corn syrup. Alarmingly, processed foods which are low in nutrients and high in sugar, fat and salt have increased to 62% of the total average Canadian diet. The ever continuing increased intake of processed foods has escalated sugar intake dramatically from 4 pounds per person per year 200 years ago to 151 pounds per person per year today (10).

What conclusions can we make from all this? The worrying increase of processed foods, with their hidden excessive amounts of sugar and fat, along with our burgeoning taste for calorie- and fat-rich cheese and meats encourages us to fill our bodies with nutrient poor, high calorie foods, effectively leaving little room on our plates or in our stomachs for the healthy whole foods upon which we could be thriving. Our fat level is still too high; our sugar level is without a doubt disturbing. The bottom line is that in our stressful and high paced world, foods high in calories, fat, sugar and sodium are just too available, quick and easy to eat making the more healthful whole foods seem to be too much trouble. If we care about our health and our future, we need to take a deeper look into how exactly we are fueling our bodies. Isn’t our well-being worth whatever it takes to eat nutritious food?

Is it genes, medical conditions or environment?

You may feel that you have a predisposition for gaining weight. Have you heard the saying, “Genetics load the gun; environment pulls the trigger.”? This runs as true for body weight as it does for chronic diseases. Gaining weight is not your destiny. Although obesity does seem to run in families, you have to remember that families share diet and lifestyle habits as well as genes. Though genes can definitely play a part in obesity, the happy news is that environment and lifestyle can alter these genes. Epigenetics is the study of how the expression of genes can be modified by factors such as environment and lifestyle. In other words, you cannot exchange your old genes for new and healthier ones but the genes you have do not have just one predetermined outcome. A gene mutation that might lead to excess weight doesn’t have to come to pass. You can modify its fate through lifestyle (11,12). Remember, it is you who is in control of what you put into your body.

It is estimated that medical conditions that actually cause obesity account for only about 1% of all cases. Such medical conditions could include hypothyroidism, Cushing’s syndrome, depression and some neurologic problems. Some drugs, such as steroids and antidepressants are also associated with obesity.

To be continued…..



www.statcan.gc.ca.  Body mass index, overweight or obese, self-reported, adult, by age group and sex (Number of persons)

2  Lauren Streib.   World’s Fattest Countries. February 8, 2007. Forbes.

3   Lau, D.C., Douketis, J.D., Morrison, K.M. et al.  2006 Canadian clinical practice guidelines on the management and prevention of obesity in adults and children [summary. CMAJ 2007. 176 (8): S1–13.

4   Yang, L, Colditz, G.A.  Prevalence of Overweight and Obesity in the United States, 2007-2012. JAMA Intern Med. 2015 Aug; 175(8): 1412-1413.

5  Berkow, S.E., Barnard, N.  Vegetarian Diets and Weight Status.  Nutr Rev 2006; 64(4): 175-188.

6  Farmer, B., Larson, B.T., Fulgoni, V.L. et al.   A vegetarian dietary pattern as a nutrient-dense approach to weight management: an analysis of the national health and nutrition examination survey 1999–2004. J Am Diet Assoc. 2011 Jun; 111(6): 819–27.


8  Barnard, N.  Trends in food availability, 1909–2007.   Am J Clin Nutr May 2010; 91(5):  1530S – 1536s.

9  Guidelines on the collection  of information on food processing  through food consumption surveys. Rome, 2015.  Food and Agriculture Organization of the United Nations.

10  Obesity in Canada; A Whole-of-Society Approach for a Healthier Canada.  March, 2016.  Report of the Standing Senate Committee on Social Affairs, Science and Technology

11 Stöger, R.  Epigenetics and obesity.  Pharmacogenomics. 2008 Dec; 9(12): 1851–1860.

12  Herrera, B.M., Keildson, S., Lindgrena, C.M. Genetics and epigenetics of obesity.  Maturitas. 2011 May; 69(1): 41–49.

13  Toth, M.J., Poehlman, E.T., Sympathetic nervous system activity and resting metabolic rate in vegetarians. Metabolism. 1994 May; 43(5):621-5.

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Promoting a healthy adventurous lifestyle powered by plants and the strength of scientific evidence.

My name is Debra Harley (BScPhm) and I welcome you to my retirement project, this website. Over the course of a life many lessons are learned, altering deeply-rooted ideas and creating new passions.

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