Fats Fact and Fiction

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					 Fats: Fact and Fiction

Gretchen Gruender MS, RD, CD
 Seattle Cancer Care Alliance
          Pouring over the fats

•   Dietary fat and cancer
•   Role of fats in our body
•   Types of fat
•   Sources of fat in food
•   Cooking with fat
                   Cancer Survivors
Increased risk for lingering effects:
   – Body composition changes
        • Weight gain, weight loss, changes in body composition
   –   Accelerated bone loss / Osteoporosis
   –   Diabetes
   –   Congestive heart failure
   –   Changes in bowel function
   –   Taste and smell changes
   –   Hot flashes
   –   Neuropathies
   –   Hyperlipidemia
   Where can the quantity and quality of fat make a
     Women’s Intervention Nutrition
     Study (WINS): Study Results
          Does a low fat diet prevent breast cancer (BC) recurrence?
•   2437 women with early stage resected BC
•   48 to 79 years old
•   Randomized to one of two groups:
     – Low fat diet (~15% total calories) - ~33 gm total fat
         • 8 individual counseling sessions with Registered Dietitian
           (RD), then every 3 month contact with RD, monthly and
           quarterly group classes
     – Control – ~51 gm total fat
         • 1 individual counseling session, then every 3 month contact
           with RD
•   Median follow-up of 5 years

                                  Chlebowski, J Nat’l Cancer Inst 98, 2006
Women’s Intervention Nutrition
Study (WINS): Study Results

 24% reduction in breast cancer
recurrence in the low fat diet group
   compared to the control group
 Nutrition and Lifestyle Studies

Prostate cancer intensive nutrition & lifestyle change study:
• almost vegan diet
    – very low meat intake
    – high fruit and vegetable intake
• reduced fat
• lifestyle interventions: yoga, exercise, meditation and support groups

After one year, participants had no need for conventional therapies
    – lower PSA’s
    – greater quality of life
    – less in vitro prostate cancer cell growth
                                                        Dean Ornish, 2005
       Role of Fat in our Body
• is a nutrient
• is a source of energy
• adds taste and texture to
• makes us feel full longer
• helps absorb fat-soluble
  vitamins (A, D, E, K)
• Regulates immune
  function, inflammation
  and cell membrane
             Types of Fat
Polyunsaturated fats

Monounsaturated fats

Saturated fats

Trans fats
 Foods Have a Mixture of Fats

 Corn Oil

 Olive Oil                                   PUFA
   Butter                                    TFA/Other


         0%   20%   40%   60%   80%   100%
               Types of Fat
Polyunsaturated fats
• Essential because our bodies need but cannot make

• Polyunsaturated fatty acids: 2 types
   – Omega-6: linoleic acid (LA)
      • AA (Arachadonic acid)- eicosanoids
   – Omega-3: alpha-linolenic acid (ALA)
      • DHA/EPA (docosapentaenoic
        acid/eicosapentaenoic acid)
       Essential Fatty Acids
The ratio of omega-6 to omega-3 is more
 important than the absolute amount of
    Was 1:1 or 2:1        Now 15:1 or 20:1
          Essential Fatty Acids
Role of omega-3 fatty acids in chronic disease

•   Cancer
•   Cardiovascular disease
•   Rheumatoid arthritis
•   Diabetes
•   More…
              Fats in Food
• ALA: flaxseed oils, walnuts, hemp and chia
  seeds, legumes, green leafy vegetables,
  canola, soybean, black current seed oil, algae
• EPA and DHA: oily cold-water fish such as
  herring, tuna, sardines, anchovies and
  salmon, grass-fed meats/poultry and eggs
• ALA has to be converted in our bodies to
              Fats in Food
Conversion of ALA to DHA and EPA is
  inefficient and is reduced with:
• High intake of omega 6 fatty acids
• Alcohol
• Trans fat

It is estimated that only 2-5% of ALA is
   converted to EPA/DHA.
              Fats in Food
• LA: corn, soy, sunflower and safflower oils,
  processed foods and grains
• AA: beef, pork and poultry
             Fats in Food
Olive oil
canola oil
                  Fats in Food
Saturated Fats

Examples: butter, cakes and pastries, chocolate
  bars, coconut, coffee creamer, meat, poultry,
  dairy products, coconut oil
                         Fats in Food
Trans Fats
•   Made by hydrogenating
    vegetable oils
•   More dangerous than saturated
    fats in the body
     – Increases inflammation
     – Inhibits the conversion of
        ALA to DHA
     – Makes membranes more
     – Interferes with intercellular
     – Increases LDL cholesterol
     – Increases insulin resistance
                Fats in Food
Trans Fats
• Most found in processed foods
  – French fries, potato chips, donuts, cookies,
    crackers, cereals, shortening, muffins, pizza
    crusts, buns, cakes, fish sticks
               Read labels!!!!!
A product can say trans-fat free and still have
              hydrogenated oils.
                Fats in Food
                What’s next?
•   Fully hydrogenated fat
•   Inter-esterified fats
•   Genetically modified seed oils
•   Tropical oils
•   Partially hydrogenated with low Trans Fats
   How do we damage fats?
             Refine, oxidize, heat

Refining grains, nuts and seed oils
• Creates a colorless, flavorless oil
• Destroys/removes micronutrients
• >180 degrees C – fatty acids are oxidized
• >240 degrees C – trans fat is formed
            Preparation of oils
How are oils extracted from the nut/seed?
• Cold pressing: mechanical process - maximum
  temperature of 172 degrees
• Heat pressing: mechanical process – temperatures
  between 208-280 degrees. Oil from this method will
  be treated with a solvent, and may go through
  degumming, refining, neutralizing, bleaching,
  hydrogenating, or deodorizing.
          Cooking with Fats
• If possible, choose oils
  that have not been
  refined, expeller pressed
  or extracted with
• Best options:
  unrefined and/or cold
• Avoid exposing oils to
  heat, light and air
          Cooking with Fats
• Do not exceed the smoke point of an oil
• PUFA’s are not tolerant of high temperatures
• Better choices for cooking at high heat
  include peanut, sunflower and canola oil
• Avoid cooking with cold pressed oils and
  reserve for vinaigrettes
           Cooking with Fats
• Purchase nuts and seeds raw and in a shell
  if possible
• Store in a cool, dark place

Best choices for fish:
  – Wild salmon, cod, sardines, small tuna or
    How much is enough?
20 – 35% of total Calories from fat

2000-Calorie diet
         = 44 – 78 grams of fat
                or 11 – 19 ½ teaspoons
1500-Calorie diet
          = 33 – 58 grams of fat
                or 8 ¼ – 14 ½ teaspoons
Ways to decrease your overall fat intake:

• Use higher fat foods as “condiments”
   – Grate cheese on vegetables
   – Add a handful of granola to fruit
   – Add a small handful of nuts to a salad
• Most fruits, vegetables, grains and legumes have
  very small amounts of fat – enjoy an abundance of
  these foods.
• Decrease the amount of meat that you eat
• Take the skin off chicken and turkey
Ways to decrease your overall fat intake:

• Before sautéing, warm your pan slightly before
  adding vegetable oil – the oil will disperse in the
  pan quicker if it is warm which may result in
  using less oil
• Minimize eating processed foods such as crackers,
  cakes and microwavable meals as they are
  generally higher in fat than whole foods.
• Eat real cheese but eat it in small amounts, not at
  every meal, not daily
Ways to decrease your overall fat intake:

• Use low fat or nonfat dairy, or eat smaller amounts
  of whole fat dairy
• If you buy large quantities of nuts or vegetables
  oils (like olive oil), put a small amount in a
  separate container to use daily. Studies show we
  serve 22% more volume of food when we dispense
  food from a larger container.
• Practice mindful eating – don’t buy a bid bag of
  nuts and eat them in the car while you are driving
  to work, talking on the phone, etc.
             Cooking with Fats
Recipe: Triple A Salad

Smell and Taste