Chapter 10 Lecture
Eating Well
Guidelines to Good Eating
• The healthiest diets include:
• Fruits and vegetables
• Whole grains and high-fiber foods
• Fish, especially seafood rich in omega-3 fatty acids, consumed twice weekly
• Saturated fats limited to less than 7% and trans fats to less than 1% of daily needs
• Fat free or low-fat milk and dairy products
• Small portions of meat and poultry
• Minimal amounts of solid fats and foods with sugar and salt
• Alcoholic beverages consumed in moderation
Dietary Guidelines 2010
• Dietary Guidelines for the United States was first released in 1977, and focused on obtaining nutrition and avoiding food related to chronic diseases
• The 2010 Guidelines are similar to the ones released in 1977
• The focus on
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- Reducing obesity by reducing overall calorie intake and increasing physical activity
- Shifting to a more plant-based diet
- Reduce intake of food with added sugars and solid fat
- Meeting 2008 Physical Activity Guidelines for Americans
Recommended Dietary Allowance
• Recommended Dietary Allowances (RDAs) are standards set by the Food and Nutrition Board of the National Academy of Sciences
• The Dietary Reference Intakes (DRIs) improve clarity of dietary needs
• Specific recommendations will be incorporated with reference to each nutrient covered in this chapter
Necessary Nutrients
Carbohydrates
• Function – energy
• Types
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- monosaccharides
- disaccharides
- polysaccharides
• Simple breakdown – glucose is a simple form of carbohydrate
• Current DRI – children and adults consume 130 grams/day. Lack of this nutrient for women can cause fat metabolism interference (ketosis)
Carbohydrates
Glycemic Index (GI)
• This is an alternative system for classifying carbohydrate-containing foods
• The GI is based on how food affect post-prandial glycemia
• Several studies have demonstrated efficacy of a low GI diet in reducing obesity
• Fruits, nuts, whole grains tend to have low GI
• Long term benefits of a low GI diet appears to increase HDL, reduce triglycerides, and lower insulin demands
Protein
• Function - growth/maintenance of tissue
• Created from 9 essential/11 nonessential proteins = 20 amino acids
• Types – Complete/Incomplete Proteins
• Women need 1 gram/kg of body weight/day
• Beware of over-consuming protein amounts due to the nitrogen factor and extra fat storage
Fats
• Known as “lipids”
• Function - insulation, carrier of vitamins, storage of long-term energy, and satiety
• Value – 9-11 kcal/gram
• Types - saturated, monounsaturated, polyunsaturated
What are Trans Fats?
• This is a process where manufacturers pump hydrogen into vegetable oils to produce hydrogenated oil
• Trans fat has been associated with increasing LDLs in the bloodstream
• Manufacturers are now required to list trans fatty acids in the Nutrition Facts Panel on food labels
Necessary Nutrients
Vitamins
• Organic compounds needed in small amounts for normal growth, reproduction, and maintenance of health
• There are 13 different types of vitamins
• Types - 9 water (BC) and 4 fat (ADEK) soluble
• Serve as co-enzymes
• Caution when boiling vegetables since minerals can be lost due to this process
AntiOxidants
• Vitamins C, E, and beta-carotene are known anti-oxidants
• May prevent/slow the development of cancer
• May help ward off other diseases such as “age-related changes”
• Protects cells against damage by oxygen molecules called “free radicals”.
• Women should consume fruits and vegetables rich in these antioxidants to reduce certain cancers and heart disease
Minerals
• Inorganic materials act as structural elements and regulator of numerous body processes
• Found in plant and animal sources
• Seven minerals are included in the RDAs
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- Macrominerals (Major minerals): calcium, magnesium, phosphorous
- Trace minerals: iron, zinc, iodine, selenium
Minerals Calcium
• 99% of calcium in a woman’s body is found in bone & about 90% of adult bone mass is acquired in girls by age 18
• Osteoporosis (demineralization of bone) is a serious threat to 44 million Americans
• Of the 10 million who have the disease, 80% are women
• Calcium intake has the greatest influence during childhood and elderly years for women
Iron
• Iron helps build certain enzymes and proteins in the body
• Humans need 10-12 mg of iron/day to manufacture hemoglobin
• Women need as much as 18 mg/day or higher due to blood loss from menstruation
• Two forms of iron found in foods
• Heme iron (animal sources)
• Nonheme iron (plant sources)
Water
• Over half the body’s weight is composed of water
• Function – provides medium for nutrients, waste transport, temperature control
• RDA – Women should drink at least 6 glasses per day, even though water is extracted from other food products
• Thirst is regulated by the concentration of sodium in the blood
Phytochemicals
• These are substances in plant food that act on the body’s physiology in some positive way
• Refer to Table 10.4 to see how these chemicals act as a protector against certain diseases or ailments
• In the near future, phytochemicals could be classified as essential nutrients
Pregnancy and Breast-feeding
• Energy Needs during Pregnancy
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- Average weight gain of a normal weight woman: 25-35 pounds
• Nutrient Requirements during Pregnancy
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- Increased Protein intake
- Iron deficiencies
- Folacin deficiencies and birth defects
- Calcium and Vitamin D
- Vitamin and Mineral Supplementation
Dietary Guidelines for Pregnancy
• Women who are capable of becoming pregnant should choose foods with
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- Heme iron
- Additional iron sources
- Vitamin C-rich foods
• Women who may be pregnant should refrain from drinking alcohol
• Women who are pregnant or breast-feeding women should consume 8-12 oz of seafood per week from a variety of types
Physical Activity
• Fitness activity levels have an effect on a woman’s nutritional needs.
• Caloric intake
-
- If you are involved in some form of activity, your energy intake should match your energy expenditure unless you are attempting to lose weight
• Nutrients
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- Exercise increases the athlete’s need for more energy and water, not for more protein, vitamins or minerals
Vegetarianism
• Relies on plant sources for most of the nutrients the body needs
-
- Ovo – use of eggs to supplement protein needs
- Lacto – use of milk products to supplement protein needs
- Semi vegetarian – great reduction of meat products but still consumes meat products
- Vegan – removal of milk, eggs, and animal products from their diet which requires a high level of nutritional understanding
• Complementary foods are needed to maintain protein, iron, calcium, vitamin D, and vitamin B12 intake
Benefits of Vegetarianism
• Leanness
• Lower levels of serum cholesterol
• Reduced risk of cardiovascular disease
• Lower mortality rate
Concerns of Vegetarianism
• Iron deficiency
• Insufficient levels of calcium
• Vitamin D deficiency
• Vitamin B-12 deficiency
Nutrition and the Consumer
Food Additives
• Many women are concerned about the amount of additives found in foods
• Additives are chemicals in food that are unnatural
• They are used for 5 principle reasons:
• Maintain product consistency
• Improve/maintain nutritional value
• Reduce spoilage
• Provide leavening or control alkalinity
• Enhance flavor/provide color
Organic Foods
• Organic foods are grown without the use of commercial chemicals
• Contribute to a more sustainable environment
• Are some organic products more beneficial than others? Get the facts!
• Compare farmer’s markets to supermarkets
• Buying locally can also help sustain the environment
Food Labeling, Food Safety, & Managing Weight Through Nutrition
• One pound of fat equals 3,500 kcals
• Exercise is crucial to a weight management program
• Proper weight management is a lifetime lifestyle commitment
• Fad diets and weight loss programs are not the answer to weight management
• There is no fast way to weight loss
• Weight management through medications does not work
Underweight, Overweight, and Obesity
• More than 64% of adult men and women in the U.S. are overweight or obese.
• Nature vs. Nurture Theories
• Research has linked obesity to genetic, biochemical, metabolic, psychological, and physiological factors
Weight Loss
• Dietary Guidelines for Americans 2010, recommends balancing foods and beverages with calories expended to maintain body weight and making small decreases n food/beverage calories and increasing physical activity to prevent gradual weight gain over time.
• Popular Commercial Diets
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- Extreme: it is often difficult and expensive to follow such restricted ways of eating over long periods
• Dieting versus Balanced Food Intake
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- Basal metabolic rate - the amount of energy you need to maintain your body functions, will decline about 2% after the age of 30
Nutrition and the Aging Population
• Understanding about nutritional needs for women over the age of 65 is essential
• People over the age of 65 account for 13% of the U.S. population
• Of this amount, 85% have nutrition-related problems such as hypertension, osteoporosis, heart disease, and type-2 diabetes
• Most older women have a diet containing about 1,300-1,600 kcals/day
• Older women need additional amounts of
• Vitamin D
• Vitamin B-12
• Folate
• Calcium
Recommendations for Older Women and Nutrition
• Use the USDA ChooseMyPlate as a reference (see Figure 10.1)
• Drink adequate - not excessive amounts of water
• Decrease fat consumption and increase nutrient dense foods such as fruits and vegetables
• Take supplements to provide nutrients not consumed in foods
• Obtain higher levels of specific nutrients such as Vitamin D and Calcium
• Maintain a physician -approved exercise regimen to strengthen bones and muscles, promote sleep, and improve appetite