KNES 237 Midterm 2 Flashcards
Disordered eating
- restricting, purging, steroid use
- weight and shape preoccupation
- striving for perfection, fasting
- yo-yo dieting, excessive exercising
- compulsive exercising, laxative abuse
Eating disorder
Anorexia nervosa, bulimia nervosa, binge eating disorder
Eating disorders- Family
History of dieting/eating disorders
history of depression/anxiety/alcohol dependence
history of obesity
Eating disorder- Indidvidual
- female gender, genetics, premature birth, low self esteem, perfectionism, previous depression/anxiety, previous obesity, early puberty, diabetes, Crohn’s disease
Eating disorder= Possible triggers and maintaining factors
- puberty
- socio-cultural pressures
- family factors
- pressure to achieve
- behaviour of peers
- comments about weight
Clinical diagnosis of anorexia
refuse to maintain body weight at 85% of expected
intense fear of gaining weight
disturbance in body image
amenorrhea (absence of 3 consecutive menstrual
cycles)
restricting type or binge eating/purging type, restrict to very low intake of calories
Physical consequences of anorexia
- Anemia
- Low bone density
- Depression
- Amenorrhea – absence of menstruation
- Impaired immune response
- Sensitivity to cold
- Soft, thick facial hair, thinning scalp hair
- Low blood pressure
- Irregular slow heart rate, loss of muscle tissue
Features of anorexia
- Individuals with anorexia nervosa typically severely restrict their food intake and may exercise intensely
- Some turn to self-induced vomiting after eating
- Family members and friends often report high levels of anxiety
- People with anorexia are often “model students” or “ideal children,” but in their personal lives may experience low self-esteem, social isolation, and unhappiness
How common is anorexia
- Approximately 1% of young women and <0.1% of young men have anorexia nervosa
- Reported in girls as young as five and women through their forties
- It usually begins during adolescence
- People at risk tend to be overly concerned about weight and food, and many attempted weight loss/dieted early
Treatment for Anorexia
- There is no treatment that cures anorexia nervosa quickly
- The disorder takes a good deal of time and professional help to treat (often years). Ongoing therapy is important for continued recovery.
- Treating the disorder is difficult because few with anorexia believe their weight needs to be increased
Treatment programs for anorexia
- Treatment programs focus on:
– Normalizing eating and exercise behaviors
– Nutritional health and body weight
– Psychological counseling for self-esteem
– Attitudes about body weight and shape
– Antidepressant or other medications
– Family therapy - Complete success in 25-50% (depending on
the study) and partially successful in others
Clinical diagnosis of bulimia nervosa
Recurrent episodes of binge eating. An episode of binge eating is characterized by both of the following:
Eating, in a discrete period of time (e.g., a 2 hour period), an amount of food that is definitely larger than what most people would eat during a similar period of time and under similar circumstances.
Lack of control over eating during the episode (e.g., a feeling that you cannot stop eating, or control what or how much you are eating).
Recurrent inappropriate compensatory behavior to prevent weight gain, such as self-induced vomiting, misuse of laxatives, diuretics, or other medications, fasting, or excessive exercise.
The binge eating and inappropriate compensatory behaviors both occur, on average, at least once a week for three months.
Self-evaluation is unduly influenced by body shape and weight.
Bulimia Nervosa
- Bulimia nervosa occurs in 1-3% of young women and 0.5% of young men.
- Bulimia nervosa often starts with voluntary dieting to lose weight and at some point voluntary control over the dieting is lost.
- People feel compelled to engage in binge eating and vomiting
- The behaviors become cyclic, food binges are followed by guilt and/or depression, purging, and dieting
- Once a food binge starts, it is hard to stop
Features of bulimia nervosa
- Unlike those with anorexia nervosa, people with bulimia usually are not underweight or emaciated
- They tend to be normal weight or overweight
- Bulimia nervosa is common among athletes
Causes of bulimia nervosa
Exact cause not known with certainty
* Depression
* Feast-famine cycles: fasts and restrained eating
(purposeful restriction in food to control weight) may cause feelings of deprivation that trigger binge
* Abnormal mechanisms controlling food intake
A way for a person with bulimia to feel more in control over their lives
treatment for bulimia nervosa
- Nutrition and counseling to break feast/famine cycles
- Eating regular meals
- Psychological counseling to improve self-esteem and attitudes toward body weight and shape
- Antidepressants may be useful
- Full recovery of women is higher than for anorexia
- Most women with bulimia achieve partial recovery
- 1/3 relapse to bingeing and purging within seven years
Binge-eating disorder
- Likely to be overweight or obese, one third being male
- Individuals eat several thousand calories’ worth of food during a solitary binge (within 2 hrs), feel a lack of control over the binges, and experience distress or depression after the binges
occur - do not vomit, use laxatives, fast or exercise excessively in an attempt to control weight gain= no compensatory behaviour(s)
- Must have binges once a week over six months to be diagnosed
Binge-eating disorder: episodes
- Binge eating episodes associated with 3 (or more) of the following:
1. Eating much more rapidly than normal
2. Eating until uncomfortably full
3. Eating large amounts when not physically hungry
4. Eating alone because of feeling embarrassed by quantity of food being consumed
5. Feeling disgusted with self, depressed or guilty
Binge-eating disorder: percents
- 9-30% of people in weight-control programs and 30-90% of individuals with obesity have binge-eating disorder
- Condition is far less common (2 to 5%) in the general population
Binge-eating disorder: emotions
- Stress, depression, anger, anxiety, and other negative emotions prompt episodes
- Binge eating disorder may be related to genetic mutation that impairs normal eating behavior
– MC4R gene mutation in 5% of individuals with the disorder
Binge-eating treatment
- Treatment focuses on disordered eating and underlying psychological issues
- Persons will be asked to record food intake and note feelings, circumstances, and thoughts related to each eating event
– Information identifies circumstances that prompt binge eating and alternative behaviors to prevent it
Pica (craving for non-food substances)
- the word pica comes from the latin word for magpie, a bird known for its unusual eating habits
- purified starch (amylophagia)
- ice cubes (pagophagia) – one case study 10 kg
- clay or dirt (geophagia)
- Largely found in children and pregnant women
- Direct or indirect cause or symptom of iron
deficiency anemia
Eating disorder resourses
- Information and services for eating disorders are available
- Services delivered by health care teams specializing and experienced
- Primary care physician, dietitian, or nurse practitioner is good start to the process
Types of carbohydrates
Simple and complex
Simple carbohydrates
- Monosaccharides and disaccharides
- few are made by animals; most are plant sourced
- Health risk: rapidly absorbed into blood stream, increased insulin resistance and inflammation
Monosaccharides
- Glucose (blood sugar or dextrose), Fructose (fruit sugar), Galactose
- Most abundant and nutritionally relevant is glucose
- Only monosaccharides are absorbed into bloodstream
Disaccharides
- Two monosaccharides joined by a covalent bond
- Sucrose, maltose and lactose
Sucrose
- cane sugar, beet sugar
- is the most widely used natural sweetener
- glucose + fructose
Maltose
- formed from the partial breakdown of starch and is often used in malt beverages (e.g., beer= barley is malted, maltose is formed, bacteria ferment the maltose and make alcohol)
- glucose + glucose
Lactose
- is “milk sugar”, one of the only animal sugars besides glucose
- Glucose + galactose
Complex carbohydrates
Oligosaccharides and Polysaccharides
Oligosaccharides
- Short chains of monosaccharides joined by bonds that cannot be broken by human enzymes (i.e. they are a fiber source)
- Fructans and galacto-oligosaccharides
- Garlic, onions, wheat, artichokes, beans, lentils, chickpeas, inulin
- most ~ 3 monosaccharide units
Polysaccharides
- Long chains of monosaccharides joined by bonds (some digestible and some
not) - Include glycogen, starch, and cellulose
- Potato, rice, pasta, corn, cereal, bread, apple peel, seeds, nuts
- up to 1000’s of units
primary nutritional polysaccharides:
Starch: energy storage in plants (digestible)
Glycogen: energy storage in animals (digestible)
Cellulose: provides structure in plants( non-digestible)
- Starch and glycogen are digestible = glucose polymers bonded with α glycosidic bonds that CAN be broken down by enzymes
- Cellulose is non-digestible = connected via β glycosidic bonds that can NOT be broken down by human enzymes
Fiber in the intestine
- Fiber is important to our health because of what happens to it in the colon.
- COLON: Bacterial enzymes can break down fiber to form short chain fatty acids and gas as a byproduct.
- Fiber feeds our gut microbiota.
Microbiota symbiosis
- high fiber whole natural foods
- gut microbiota pyramid
Microbiote dysbiosis
- Processed foods low fibre
- chronic disease pyramid
Look for whole grain foods
- In a grain of wheat, the outer bran layer is a rich
source of dietary fiber - The germ contains protein, unsaturated fats, thiamin, niacin, riboflavin, iron, and other nutrients
- The bran and germ are removed in the refining
process (i.e. making white flour) - The endosperm primarily contains starch, the
storage form of glucose in plants = white flour
Soluble fiber
- benefits health in several ways
- Slows down glucose absorption, thereby lowering peak blood levels of glucose
- reduces fat and cholesterol absorption
- Found in oats, barley, fruit pulp, peas, beans, citrus fruits, strawberries and psyllium
- Lower calories than digestible carbohydrates (1-2 kcal/g typical)
Insoluble fiber
- Insoluble fiber is good because it benefits health in several ways
Moves bulk through gut, controls gut pH, removes toxic waste, prevents constipation - Found in vegetables, wheat bran, whole grains, flax seed, popcorn, corn bran, seeds, nuts, apple peel
Macronutrient effects on blood glucose
How does the body manage glucose:
1. Blood glucose rises when you eat.
2. High blood glucose stimulates pancreas to release insulin.
3. Insulin stimulates uptake of glucose into cells and storage as glycogen in liver and muscle. It
also helps convert excess glucose into fat stores.
4. As body cells use glucose, blood levels decline.
5. Low blood glucose stimulates pancreas to release glucagon.
6. Glucagon stimulates liver cells to break down glycogen and release glucose into blood.
7. Blood glucose begins to rise
Added sugars
- Major sources of simple sugars in most diets are added during processing of food
- Labels contain information on total sugars per serving but do not distinguish between naturally occurring and added sugars yet.
- ‘Added sugars’ add calories without adding nutrients
The bad side of sugar
We need sugar to survive, but…
- Tooth decay
- Empty calories (calories without nutrients)
- Often mixed with fats in sweets
- Limit sweet and sticky foods; replace them with vegetables and fruits
- Overall quality of diet decreases when sugar intake increase
Sugar alternatives
- Alcohol sugars (~2.6 kcal/g)
Xylitol
Mannitol
Sorbitol - Used in chewing gum and other candies and foods
- Can be used to mask the unpleasant aftertaste of some artificial sweeteners
- Are not well absorbed in the gut; large amounts can cause diarrhea
Stevia
- Herbal Alternatives: Stevia (GRAS – generally recognized as safe - status)
- Initial studies with crude whole leave extracts of stevia = reproductive, renal and cardiovascular toxicity
- Purified stevioside preparations show no toxic effects
- In 2012 Health Canada approved its use in foods
Artificial sweeteners
Aspartame, sucralose, Acesulfame K, saccharin
Aspartame
A dipeptide (2 amino acids = aspartic acid + phenylalanine)
Digestion releases methanol (10%), aspartic acid (40%) and phenylalanine (50%)
Methanol converted to formaldehyde and then formic acid
200 times sweeter than sucrose (sugar)
Products containing it bear a “contains phenylalanine” label for people with PKU (phenylketonuria)
“Nutrasweet” & “Equal”
Acceptable daily intake 40 mg/kg BW
Not compatible with high temperatures (> 30ºC)
Sucralose
- Made from sugar = chlorinated sugar
- 600x sweeter than sugar
- Safe when heated
- “Splenda”
Acesulfame K
- Often used in combination with other artificial sweeteners
- Stable at high temperatures
Saccharin
Discovered in 1879 by accident by chemist working on coal tar derivatives
- 300x sweeter than sucrose
- Banned in Canada in 1977 due to bladder cancer fears, returned to market once it was discovered the mechanism by which it caused
cancer in rats is not present in humans.
maternal artificial sweetener consumption during pregnancy
- Reduced insulin sensitivity
- Altered mesolimbic reward pathway in the brain
(promotes food seeking behavior) - Altered gut microbiota composition and function
- Offspring had 25% higher fat mass at 3 weeks of age
Sugar and Tooth decay
A. Mechanism
B. Promoters of tooth decay
C. Protective foods
D. Fluoride and dental health
A. Mechanism
- sugar is sole food for bacteria -> produce acid
- bacteria form sticky white plaque
- acid is produced by bacteria for 20 min after
sugar is eaten
B. Promoters of tooth decay
- increased frequency of sticky foods
- acidic beverages
- excessive cleaning/polishing of teeth
- nursing bottle syndrome
C. Protective foods
- cheese (increases ph of plaque- decrease acidity)
- protein (with calcium it strengthens enamel
- low calorie sweeteners such as orbital, mannitol, xylitol (stimulate saliva)
D. Fluoride and dental health
- promote remineralization of eroded enamel
- water, toothpastes, dental rinses
- excess leads to fluorosis or “mottled” enamel during tooth development
- cosmetic condition that can only form in children less then or equal to 8 years when permanent teeth are developing
Fluoride in drinking water
2011 City of Calgary voted to remove fluoride from water supply
2016 study compared rates of tooth decay in grade 2 children from Calgary (removed fluoride) and Edmonton (kept fluoride)
Compared 2004/2005 and 2013/2014 data
Both cities had high rates of tooth decay but was increasing more rapidly in Calgary
2021 study shows gap is widening: “Of the approximately 2,600 Grade 2 students in each city who took part in the study, 55.1% of
Edmonton participants had one or more cavities in their baby teeth. In comparison, the number was 64.8% of Calgary children.”
November 2021 City of Calgary voted to reintroduce fluoride into water supply (set to start by September 2024)
Gestational diabetes
Only during pregnancy
Type 1 (insulin- dependent) Diabetes
- typically diagnosed before 40, abruptly
- treatment is with insulin, diet and exercise
Type 2 (non-insulin dependent) diabetes
- lifestyle related
- treatment is weight reduction
Diabetic symptoms
Poorly controlled, untreated diabetes produces:
Blurred vision
Frequent urination
Weight loss
Increased susceptibility to infection
Slow healing sores
Extreme hunger and thirst- cells being stared from glucose
Diabetes: health consequences
Long term, diabetes may cause:
Heart disease and stroke
Kidney damage (nephropathy)
Blindness (retinopathy)
Nerve damage (neuropathy)
Loss of limbs due to poor circulation
Alzheimer’s disease
Insulin
Insulin is a pancreatic hormone
Reduces blood glucose
Facilitates passage of glucose into cells(T2D)
Low/no insulin (T1D) starves cells
Cells can also starve if cell membranes become insulin- resistant (T2D)
Gestational diabetes
- 5 to 6% of women develop gestational diabetes
- Indigenous and Black, women with obesity, women over 35 years, and women with low physical activity have greater risk
- Women with gestational diabetes are insulin resistant
- Control blood glucose levels with an individualized diet and exercise plan
Gestational diabetes 2
- Infants of women with diabetes may have increased body fat at birth & have blood glucose control problems after delivery
At greater risk for diabetes later in life
6 to 20% will have a physical abnormality that may threaten survival or a high quality of life
e.g. cleft palate, club foot, heart defects - some women require daily insulin injections for blood glucose control
Gestational diabetes after pregnancy
Gestational diabetes disappears after delivery
But type 2 diabetes may appear later in life in the mom
Exercise, maintenance of normal weight, and a healthy diet reduce the risk that diabetes will return
Type 1 diabetes
Type 1 diabetes results from a deficiency of insulin
Accounts for about 5-10% of all diabetes and is increasing yearly (2x as high as children in ’80s)
Diagnosis of type 1 peaks around the ages of 11 to 12 years and usually occurs before age 40
Autoimmune disease that destroys pancreatic beta-cells that produces insulin
Breastfeeding for first four months may protect infants against type 1 diabetes
Environmental factors are more important than genetics in type 1 diabetes
Candidates have included: early exposure to cow’s milk proteins; vitamin D deficiency; early exposure to gluten; certain viruses (rubella, rotavirus, mumps, cytomegalovirus, enteroviruses); gut microbiota
Immune-mediated diseases and microbiota
- Finland highest rate of type 1 diabetes in the world.
- in different regions around 8 times lower incidence
- share similar genes but different hygiene/microbial exposure
- Estonia, once lower, is catching up with Finland
managing type 1 diabetes
- Insulin
Injections
Pump
Islet transplant - Diet
- Exercise