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Discover the impact of the Standard North American Diet on health and how to prevent chronic illnesses through balanced nutrition. Learn about essential nutrients, the Healthy Eating Index, and the benefits of whole foods for optimal well-being.
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The standard North American Diet is a significant factor in the rising rates of chronic illness
Percent of diseases potentially preventable with diet and lifestyle change Balancing Life-Style and Genomics Research for Disease Prevention by Walter Willet
What’s wrong with the standard North American Diet? • Highly processed foods tend to have poor nutrient density and low fiber content • Nutrient poor diets lead to multiple nutritional deficiencies/insufficiencies • Nutritional deficits have real effects on population health
Common nutrient deficiencies in N.A. • Calcium • Iron • Magnesium • Zinc • Vitamin E • Vitamin A • Copper • Omega 3 fatty acids • Vitamin D • Fiber • Vitamin C • Vitamin K • Potassium • Vitamin B6
Healthy Eating Index • In a survey of 8,272 people done by the National Health and Nutrition Examination Survey (NHANES 2003-2004), the average healthy eating score for people age 2 and older was 57.5 out of a possible score of 100.
What else is wrong with the Standard North American Diet? • There tends to be an excess of: • Trans fats • Saturated fats • Omega 6 fatty acids • Sodium • Phosphorus • Protein • High GI carbohydrates, including added sugars, high fructose corn syrup etc
Vulnerable groups • The elderly • Aboriginal populations • The poor • Alcoholics • Patients with chronic disease • Adolescents/teen mothers • Hospitalized patients • Vegans
Essential nutrients: nutrients we require but cannot synthesize • 9 amino acids (10 in children) • An energy source • 2 fatty acids • 13 vitamins • ~21 minerals • Water • Oxygen
Macronutrients(carbohydrates, fats, protein) Most North American diets have ample quantities of carbohydrates (mainly from starchy foods such as bread, rice, pasta), fats (cooking oils, margarine, butter, fried foods, added fats in baked goods), and protein (meat, milk, cheese, yogurt, fish)
Problems with macronutrients in typical North American diet • Carbohydrates: poor quality (low nutrient density), high glycemic index, low fiber, contain other harmful substances (e.g. trans fats) • Fats: often the ‘wrong kinds’ of fats & very little of the essential fatty acids we require • Protein: often present in excessive amounts, poor quality, containing other harmful substances (e.g. saturated fats)
Nutrient density versus calories • North American diets are rarely short of calories. The average person in Canada consumes > 2000 calories per day. • In order to improve the nutritional content of our diet, we must, therefore, consume more nutritionallydense foods. • The more ‘empty calories’ we consume, the more obese and unhealthy we tend to become.
The solution: eat ‘whole foods’ Whole foods generally have higher nutrient density than processed foods Whole foods are minimally processed with few nutrients removed and no harmful substances added
Characteristics of whole foods Whole foods do not contain added trans fats, artificial coloring agents, high fructose corn syrup, etc
Some examples of whole foods Fresh or frozen fruits and vegetables that have been minimally processed, other than to be washed, trimmed (or blanched) and then eaten either raw or cooked.
Whole foods: whole grains, legumes and nuts/seeds 1. Whole grains: wheat berries, brown rice, quinoa, millet, corn and products made from whole grains 2. Legumes: kidney beans, pinto beans, garbanzo beans, navy beans, etc 3. Nuts: walnuts, pine nuts, pecans, almonds, cashews, etc
Whole foods… Eggs, cheese, yogurt, milk, tofu, soymilk
Whole foods… Unprocessed beef, lamb, chicken, turkey and fish
Whole foods versus nutrients • Whole foods are complex mixtures of proteins, fats, carbohydrates, vitamins, minerals, enzymes, phytochemicals, fiber, water and possibly other as yet unknown constituents. • Studies repeatedly find that whole foods have actions that are different from their isolated constituents
Lycopene versus tomato powder • Rats were treated with compounds known to induce prostate cancer. They were then fed their regular diet plus either whole tomato powder, pure lycopene or placebo. • Rats fed the whole tomato powder had a significantly better chance of survival (without prostate cancer) compared with the lycopene and placebo groups (38% vs 20%) Prostate Carcinogenesis in N-methyl-N-nitrosourea(NMU)–Testosterone-Treated Rats Fed Tomato Powder,Lycopene, or Energy-Restricted Diets J Nat Can Inst Vol 95 No 21 Nov 2003
Carrots • Carrots contain over 100 phytochemicals and other substances including: aesculetin, apegenin, arachidonic acid, p-hydroxybenzoic acid, caffeic acid, chlorogenic acid, chlorophyll, chrysin, cinnamic acid, p-coumaric acid, eugenol, ferulic acid, geraniol, beta-ionone, kaempherol, limonene, linalool, linolenic acid, luteolin, methionine, myristicin, oleic acid, alpha-pinene, psoralen, 5-methocypsoralen, quercetin, quercitrin, beta-sitosterol, stigmasterol, umbelliferone, vanillic acid, etc
Carrots Carrots also contain: B vitamins (B6, thiamine, folic acid), beta-carotene, vitamin C, magnesium, vitamin E, vitamin D2, potassium, copper, calcium, glutathione, iron, manganese, phosphorus, sulfur, calcium pectate (a type of pectin fiber)
More about carrots • There are several hundred different varieties of carrots available in six different colors • The nutritional content of a carrot varies according to the variety, the soil type and quality, growing conditions, harvesting methods, storage and transportation, processing, cooking methods, etc
Sulforaphane (an isothiocyanate) content of different varieties of broccoli • Sulforaphane content can vary from a low of 1.4 mg/g to a high of to 32.9 mg/g • Variety # 26 had 23.5 x the amount of sulforaphane as did variety # 172 • Mean sulforaphane was 12.9 mg/g “Determination of sulforaphane in broccoli and cabbage by high-performance liquid chromatography” H Liang et al 2006
Whole foods versus processed foods • Processing may decrease the nutritional value of foods by removing parts of the whole food (e.g. the germ and bran of wheat), heating the food to high temperatures (e.g. oils), adding trans fats and sugars, etc
The difference between whole grain flour and enriched white flourin the content of 15 nutrients
Phytochemicals in whole grains • Whole grains contain unique phytochemicals that complement those in fruits and vegetables • These include: phenolic acid, ferulic acid, anthocyandins, quinone, flavonols, chalcones, flavones, flavanones, carotenoids, lignans, b-glucan, inulin, resistant starch, tocotrienols, tocopherols, oryzanols, sterols and phytates • Most beneficial phytochemicals (50-80%) are contained in the bran/germ of the grain
‘Whole grain’ versus ‘whole wheat’ • Definition of ‘whole grain’: If all parts of the kernel are used in the same relative proportions as they exist in the original kernel, then the flour is considered whole grain. • Definition of ‘whole wheat’: Up to 5% of the kernel may be removed. This portion contains much of the germ and some of the bran. • Wheat germ: protein, fiber, both essential fatty acids, potassium, magnesium, iron, zinc, iodine, selenium, vitamins E, K, & A, thiamine, folate, riboflavin, niacin, B6, carotenoids, sterols, etc
Extra virgin olive oil (EVOO) • Rich in polyphenols that have antioxidant and anti-inflammatory properties. • EVOO’s anti-inflammatory properties are similar to Ibuprofen. • EVOO also contains vitamin E, PUFA’s, MUFA’s, SFA’s, vitamin K, phytosterols, etc • Extra-virgin olive oil is part of the traditional Mediterranean diet
Flax oil and flaxseed Flax oil is a good source of both essential polyunsaturated fatty acids: *alpha linolenic acid (omega 3) and *linoleic acid (omega 6)
Flaxseed • Protein: 20% protein • Fiber: 28% fiber (2/3 insoluble and 1/3 soluble) • PUFA’s: Linolenic acid and linoleic acid • Phytochemicals: Lignans (phytoestrogens), beta-carotetene, lutein, zeaxanthin • Minerals: Calcium, potassium, magnesium, iron, copper, zinc, manganese, selenium • Vitamins: Vitamin C, thiamine, riboflavin, niacin, pantothenic acid, vitamin B6, folate, vitamin E • Carbohydrates
There are many kinds of salt in the world… • Himalayan salt • Celtic sea salt • Cyprus Black sea salt • Hawaiian sea salt (volcanic black) • Fleur De Sel • Bolivian Rose Salt
Unrefined sea salt vs table salt • Unrefined sea salt is ~84% sodium chloride • Unrefined sea salt also contains > 75 minerals including: sulfur, magnesium, potassium, calcium, silicon, iron, zinc, copper, manganese, fluoride, boron • However, sea salt has much lower iodine content than iodized salt (1.3 mg/g vs 68 mg/g) • Iodized table salt contains 60-99% purified sodium chloride, + anti-caking agents (calcium silicate) +/- desiccants, +/- dextrose, + iodine
Soy protein isolate versus whole soybeans • 100% less vitamin C • 100% less vitamin K • 95% less potassium • 87% less monounsaturated fat • 86% less magnesium • 85% less PUFA’s • 75% less carbohydrates • 75% less vitamin B6 • 40% less fiber • 35% less calcium • 20% less zinc • Most isoflavones are also removed
Vitamin E as found in whole foods versus supplements/food additives • In whole foods, vitamin E exists as a combination of 8 different compounds: a, b, d, g tocopherols and a, b, d, g tocotrienols • Only synthetic or natural forms of alpha-tocopherol are added to foods. • Most of the vitamin E added to multivitamins and used in individual vitamin E capsules is alpha-tocopherol
What to look for in a healthy meal: • Flavorful, appealing, colorful • At least 2 servings of fruits and/or vegetables • Adequate but not excessive calories • Reasonable balance of protein/carbs/fats • Nutrient density • Phytochemicals and fiber • Low in trans fats, saturated fats, sodium, added sugars, etc
What avoid or reduce in a healthy meal • Highly processed, nutrient depleted foods • High glycemic index carbohydrates • Trans fats • Saturated fats • Omega 6 fats • Foods containing toxic compounds e.g. heterocyclic amines, mercury, dioxins, etc
Aim for variety • Eating a wide range of colors and kinds of fruits and vegetables will provide a variety of nutrients and phytochemicals
Cooking methods: carotenoids • Carotenoids (Beta-carotene, lycopene, lutein, etc) are best absorbed from cooked vegetables eaten along with some (healthy) fat • Study: salad + fat free, low fat or regular dressing • Absorption of carotenoids from the salad with fat free dressing was negligible. • Best absorption was with the full fat dressing or with the addition of an avocado to the salad.
Cooking methods: meat and fish • Charbroiling meats or fish at high temperatures (>350°F) causes the formation of heterocyclic amines (HCA’s), toxic compounds associated with increased cancer risk. • Baking or sautéing at lower temperatures is preferable • Marinating meats or briefly microwaving them prior to putting on the barbeque can significantly reduce the formation of these compounds
Cooking vegetables • Cook greens and cabbage family vegetables lightly • Steam or sauté (preferable to boiling) • Cooking water may be used in soups and stews
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
Restaurant meals • Excess: calories, sodium, trans fats, saturated fats • Too little: nutrients (especially from fruits and vegetables) • Strategies: • Add a large salad or a double order of steamed vegetables • Avoid deep fried foods • Choose smaller portions • Eat out less often
Should you become a vegetarian? • A vegan eats only plant foods • A lacto-vegetarian eats plant foods + dairy products • A lacto-ovo vegetarian eats plant foods + dairy and eggs • A lacto-ovo-pesco vegetarian eats plant foods + dairy + eggs + fish
Vegetarian diets & cancer risk • British study of 61,556 meat eaters and vegetarians followed for more than 12 years • Vegetarians had an overall 12% lower risk of developing cancer. Some notable results: • 64% less stomach cancer • 53% less bladder cancer • 43% less non-Hodgkins lymphoma • 75% less multiple myeloma
Vegetarian diets and heart disease • In general, vegetarians have: • lower cholesterol • lower blood pressure • lower body weight • lower risk of dying from heart disease
Vegetarian diets, obesity & type 2 diabetes • Mean BMI (body mass index) is lowest is vegans, then lacto-ovo vegetarians, then pesco vegetarians, then semi vegetarians, then non-vegetarians • Even when adjusted for BMI and other risk factors, the odds ratio for developing type 2 diabetes is 0.51(vegans), 0.54 lacto-ovo, 0.7 pesco-vegetarians, 0.76 semi-vegetarians
Why do vegetarian diets have health benefits? • They do not include red meat, which has been associated in many studies with increased cancer risk • This may be related to heterocyclic amines, nitrates, saturated fat, heme iron, environmental contaminants, etc • Vegetarian diets tend to be lower in saturated fat, higher in fruits and vegetables, whole grains, nuts and beans
Good resources for vegetarians and vegans by Brenda Davis and Vesanto Melina