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A guide to healthy eating: A guide to healthy eating: the joy of whole foodsthe joy of whole foods
The standard The standard North North
American Diet American Diet is a significant is a significant
factor in the factor in the rising rates of rising rates of chronic illnesschronic 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 IndexIn 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 nutritionally dense 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
CarrotsCarrots 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 carrotsThere 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 g/g to a high of to 32.9 g/g
Variety # 26 had 23.5 x the amount of sulforaphane as did variety # 172
Mean sulforaphane was 12.9 g/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, -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, etcExtra-virgin olive oil is part of the traditional Mediterranean diet
Polyphenol content of different types of olive oil
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 ECarbohydrates
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 saltUnrefined 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 g/g vs 68 g/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 fat86% less magnesium 85% less PUFA’s 75% less carbohydrates75% less vitamin B6 40% less fiber 35% less calcium 20% less zincMost 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: tocopherols and 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 mealsExcess: 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 yearsVegetarians 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
Key recommendations 2009 Canada Food Guide
(for adults age 19-50)
7-10 servings of fruits and vegetables- at least 1 dark green and 1 orange vegetable per day
6-8 servings of grain products, with at least half being whole grains
2 servings of milk and milk alternatives- choose lower fat dairy products, choose fortified soy milk
2-3 servings of meat and meat alternatives- choose legumes often, choose fish at least twice a week, choose lean meats
The Great Plate
Used with permission from the University of Michigan, MHealthy Health & Well-Being Services
BreakfastWhole grain cereal with slivered almonds, 1% milk (or soy milk) and a banana + a glass of orange juice (or a bowl of berries)
Breakfast smoothies
Low fat yogurt, banana, strawberries, blueberries + a healthy whole grain muffin
A savory breakfast option
egg corn tortilla
sour cream (low fat)green onion, tomato salsa avocado, cheese (low fat)refried beans dash of hot sauce fresh cilantrohuevos rancheros
SummaryEat a plant based, whole foods diet
Eat a wide variety of fruits and vegetables each day (8-10 servings)
Eat whole grains, legumes, nuts and seeds
Eat fatty fish 3-4 times per week (salmon, sardines, black cod, herring, mackerel)
Choose healthy fats: extra virgin olive oil, oily fish, nuts, avocados
A diet based on a variety of whole foods = a nutrient rich diet