Healthy weight loss strategies. Dr. Louise Gagné Saskatoon Community Clinic

Transcription

1 Healthy weight loss strategies

2 Obesity in Canada Rates of obesity are rising in Canada in all age groups from About 24% of Canadians are obese Saskatchewan, the North West Territories and the Maritime provinces have the highest levels of obesity

3 Obesity rates around the world USA 34% Australia, Britain, Canada 24% Germany, Finland 16% France, Sweden, Italy 10% Japan 4% China, India 2%

4 Body Mass Index BMI = weight(kg) divided by height(m) 2 Underweight < 18.5 Normal BMI Overweight Obese 30

5 Health care costs of obesity In Canada, total medical costs of obesity = $4.3 billion/year

6 Obesity: health risks Life expectancy: women lose 7.1 years; men lose 5.8 years disability cardiovascular disease, hypertension, pulmonary embolism, stroke, CHF type 2 diabetes cancers of the breast, colorectal, prostate endometrium, kidney, ovary and pancreas

7 Obesity: health risks Dyslipidemia: cholesterol, TG s, HDL depression Osteoarthritis e.g. knee OA infertility, POS Obstructive sleep apnea Asthma Non-alcoholic fatty liver disease

8 Background information Basal metabolic rate Yoyo dieting Hormonal control of appetite Causes of obesity

9 Basal metabolic rate BMR: the rate of metabolism; the amount of energy used by the body when at rest and not in the process of digestion of food BMR= 60-75% of daily calorie expenditure Muscle tissue uses about 6 calories a day (per pound) just to sustain itself, while a pound of fat burns only 2 calories per day. Metabolic rate increases during exercise and for a number of hours afterward

10 Many things influence BMR: Males have higher BMR s than females Genetics Age: BMR declines with age Percent body fat: Higher % fat means lower BMR Starvation or abrupt decrease in caloric intake lower BMR Thyroid: hyperthyroidism higher BMR, hypothyroidism lower BMR

11 Yoyo dieting loss of muscle tissue When we lose weight, usually some fat and some muscle tissue is lost On average, about ¾ of the weight we lose is fat and ¼ is muscle. When we regain weight, about 90% is usually fat and 10% muscle Therefore: repeated dieting leads to loss of muscle tissue and lower BMR

12 Regulation of appetite Regulation of appetite is very complex The brain receives a variety of hormonal & metabolic signals from the body Hormones (produced by fatty tissue, the digestive system and the pancreas) : cholesytokinin, glucagon-like peptide, leptin, ghrelin, oxyntomodulin, peptide YY, serotonin, neuropeptide Y, insulin, etc

13 What increase appetite? Low or falling blood glucose Lack of leptin or leptin resistance Stress Lack of sleep

14 The glycemic index (GI) low 55 medium high 70

15 The glycemic load (GL) Glycemic load= GI x carbohydrate (gm per serving) divided by 100 Low 0-10 low medium high >20 GI 80 GL cup watermelon GI 72 GL 25.6 ½ bagel

16 GI/GL and weight loss 2007 Cochrane review Overweight and obese people lose the most weight on low GI/GL diets compared to other diets

17 GI/GL and appetite Obese teenage boys were fed either a high or a low GI breakfast and lunch. They were then allowed to eat whatever they wished for the rest of the day. The boys who ate the high GI breakfast and lunch experienced excessive hunger. The boys who ate the high GI breakfast and lunch ate 81% more calories (during the rest of the day) than the boys who ate the low GI breakfast and lunch.

18 Low GI carbohydrates Breads: 100% whole grain breads, pita bread, sourdough breads Rice: Basmati rice, Uncle Ben s converted rice Pasta: al dente Cooked grains: quinoa, bulgur, steel cut oats, large flake oats Cereals: All Bran Beans

19 Higher GI carbohydrates Most breads, bagels and other flour products Puffed grains Most cold breakfast cereals Potatoes Gooey starches

20 Choose high quality carbohydrates High quality carbohydrates: Low glycemic index/load Whole foods/unprocessed Nutrient dense High fiber Low in saturated fats Zero trans fats

21 Leptin Leptin is a hormone produced by fat tissue Food intake causes leptin levels to rise, the brain then senses energy sufficiency and appetite is inhibited Low leptin levels are a signal of nutritional deprivation. This triggers the body to conserve energy and increase food intake Obese persons may become leptin resistant

22 Chronic stress: influence on appetite and food choices About 70% of people increase their food intake when stressed. Most people choose calorie dense foods such as highly processed carbohydrates (pastries, chips, bread) and or foods rich in fat such as ice cream and chocolate High cortisol levels, high insulin levels, and consuming calorie dense foods all tend to promote increased belly fat

23 Stress & visceral (belly) fat Visceral (belly) fat is a source of quickly available calories, so it tends to increase in conditions of chronic stress Cortisol is released when we are stressed and higher cortisol levels are associated with more belly fat Visceral (belly) fat is linked to increased risk of coronary artery disease, stroke, hypertension and diabetes

24 Why do so many people struggle with their weight? Poor dietary choices, high glycemic index carbohydrates Availability of cheap, energy dense foods Sedentary lifestyles Inadequate hours of sleep Genetic factors Endocrine disrupting chemicals

25 Increased risk of weight gain: Frequency of restaurant meals Television viewing Household temperature Fiber intake Eating quickly/less chewing Unhealthy family functioning Use of antidepressants/antispychotic Rx Vitamin D deficiency

26 Healthy weight loss strategies Increase your BMR Avoid yoyo dieting Control appetite and cravings Get adequate sleep Eat more slowly, chew more Get enough vitamin D Reduce liquid calories and energy dense foods Reduce stress Reduce exposure to environmental toxins

27 Increase your BMR Build more muscle Move around more Do weights 2-3 times per week Go for walks Avoid very low calorie diets that promote rapid weight loss Choose diets that you could live with for the rest of your life

28 Vitamin D deficiency Vitamin D deficiency is common and obese people are more likely to be vitamin D deficient Vitamin D deficiency seems to predispose people to becoming obese Most people in Saskatchewan require supplementation with vitamin D, especially during the winter months Vitamin D IU per day with meals

29 Sleep People who sleep 5 hrs are 70% more likely to become obese compared with people who sleep 7-9 hours per night Getting 6 hours of sleep instead of 7 makes you 27% more likely to become obese Sleep deprivation leads to lower leptin levels, increased hunger and an increased preference for calorie dense, refined carbohydrate foods

30 Unhealthy family functioning Unhealthy family functioning - avoiding discussing concerns/fears, bad feelings within the family, poor support amoung family members, not being able to express sadness or other feelings, etc Unhealthy family functioning is associated with increased obesity risk behaviors : consumption of 2 cups of soft drinks per day 2 fast food meals per week processed meats 2 times per week chips 2 times per week > 3hrs per day of television viewing)

31 New research: endocrine disrupting chemicals Some insecticides and other environmental toxins can alter gene expression and alter hormonal signals, leading to an increased risk of obesity

32 Weight loss: what to do

33 As a general rule You must burn more calories than you take in, in order to lose weight!

34 Weight loss Recommended pace of weight loss is.5 to 2 pounds per week To lose one pound of fat, you need to burn an extra 3500 calories or reduce your calorie intake by 3500 fewer calories per week Therefore, to lose one pound per week, a person would need to burn an additional 500 cal/day or reduce calorie intake by ~500 cal/day In general, weight loss diets should contain at least 1200 calories

35 Carbohydrates, fats & protein A sustainable, healthy diet should not drastically increase or reduce any one food group (e.g. carbohydrates, fats) NOTE: The % of total calories from fats has decreased in the past two decades while there has been a steady increase in obesity

36 Food choices: calorie density Energy dense foods tend to contain less water and often have added fats and sugars e.g. potato chips, doughnuts Foods with low energy density tend to have a higher water content and no added sugars and fat e.g. fruits and vegetables People tend to consume a constant volume of food at a given meal Thus, energy density can influence calories consumed

37 Choosing foods that have low energy density Fruits Vegetables Whole grains Legumes: peas, beans, lentils Fish, skinless poultry, low fat dairy products, egg whites

38 Food choices: cost of a calorie One dollar will buy: 1200 calories of potato chips or 250 calories of carrots 875 calories from a soft drink or 170 calories from fruit juice from concentrate Obesity promoting foods= foods that offer the most calories at the lowest cost

39 Eating breakfast Eating breakfast is associated with a lower risk of obesity Eating breakfast has also been found to increase overall nutrient intake, particularly for fiber, vitamin A, vitamin C, vitamin E, calcium, iron, folate This is especially true for children, adolescents and young adults

40 Chewing Obese people have been found to eat more quickly and chew less In studies, people who chew more eat about 12% less food Increased chewing reduces hormones that stimulate hunger

41 Fiber and weight loss Eating more fiber is associated with weight loss Both insoluble and soluble fiber are helpful for weight loss One recent study showed that for each 1 gram increase in fiber intake, weight decreased by 0.25 kg (about ½ pound)

42 Sugar sweetened beverages (SSB s) SSB s significant contribute significantly to weight gain and can lead to increased risk of T2DM and cardiovascular disease. Calories from SSB s are less filling than calories from solid foods. SSB have a high glycemic load which can promote inflammation & insulin resistance

43 Are there fattening foods? (A) Foods associated with weight gain: potato chips, potatoes, sugar sweetened beverages, red meats, processed meats, refined grains, desserts, trans fat (B) Foods inversely associated with weight gain: vegetables, whole grains, fruits, nuts and yogurt People who ate more (A) foods and less (B) foods gained an additional 3.93 lbs

44 Other findings from the NEJM study An increase in physical activity was associated with less weight gain Weight gain was associated with: An increase in alcohol consumption Sleep duration of <6hrs or >8hrs Television watching Recent smoking cessation Changes in Diet and Lifestyle and Long-Term Weight Gain in Women and Men Mozaffarian et al NEJM June 2011

45 Liquid calories In the NEJM study, consumption of all liquids except milk was positively associated with weight gain Beverages now account for ~ 21% of calories consumed Liquid calories have been found to be less satiating than calories from solid foods

46 Conclusions Beyond eat less and exercise more there appear to be specific diet and lifestyle behaviors that can prevent weight gain Dietary quality influences dietary quantity!

47 Weight loss diets

48 Weight loss diets

49 All weight loss diets work equally well? Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Risk Reduction JAMA 2005 Results: Each popular diet modestly reduced body weight and several cardiac risk factors at 1 year.

50 All diets may work equally well in terms of weight loss, but Other factors to consider: Overall diet quality: are there enough fruits & vegetables, healthy fats, whole grains, fiber, etc Ease of adherence to the diet: e.g. is it monotonous? Cost of the diet: e.g. does it involve buying specially prepared foods, supplements, etc Does the diet support long term, sustained weight loss? Total health effects: does the diet support heart health, bone health, prostate health, etc.?

51 Low carbohydrate, high fat diets Low carbohydrate/high fat diets generally have lower diet quality Healthy eating index (HEI), low carb diet= 44.6 whereas high carb diet= 82.9 In population studies, low carb/high fat diets are associated with higher BMI s, whereas people on high carbohydrate diets are more likely to have BMI <25 Low carb/high fat diets are less likely to produce sustained weight loss

52 High carbohydrate/ pyramid group Carbohydrates > 55% of energy Fats 30% At least one serving per day from all 5 food groups in the USDA food pyramid: grains, vegetables, fruits, milk, meat & beans

53 Tips for losing weight: part 1 Eat regular meals and always eat breakfast Each meal should contain: A low glycemic index/load carbohydrate (e.g. 100% whole grain bread, al dente pasta, large flake oatmeal) Some protein (e.g. lean meats, fish, low fat dairy products, eggs, legumes) Some healthy fat (e.g. extra virgin olive oil, canola oil, nuts, avocados) At least 2 servings of fruits and vegetables

54 Recommended proportions: Used with permission from the University of Michigan, MHealthy Health & Well-Being Services

55 Tips for losing weight: part 2 Get regular exercise: aerobic exercise and weight training are both useful Aerobic: cycling, running, walking, swimming, cross country skiing, dancing Weight training: Watch your technique/consult a fitness trainer or physiotherapist Do every second or third day (2-3 x per week) Excellent for bone health as well!

56 Tips to lose weight: part 3 Obtain adequate protein Get sufficient vitamin D Get enough sleep Consume fewer sugar sweetened beverages and liquid calories (other than milk) Eat more fiber Eat out less often Eat more slowly/chew more Reduce television viewing Reduce exposure to endocrine disrupting chemicals

57 Recommended reading

58 Reliable books about the glycemic index: by Jennie Brand-Miller, et al