Weight Loss Flashcards
What is the definition of ‘Diet’?
The sum of food and drink they habitually consume.
What does dieting refer to?
The practice of attempting to achieve or maintain a certain weight through nutritional intake.
What factors can affect people’s dietary choices?
- Ethical beliefs
- Religious beliefs
- Clinical needs
- Economic factors
What is a vegetarian diet?
A diet that excludes meat and animal by-products.
What are the types of vegetarian diets?
- Fruitarian diet: raw fruit
- Lactovegetarian: certain dairy, excludes eggs
- Lacto-ovo vegetarian: includes eggs and dairy, excludes animal flesh
- Vegan diet: contains only plants and foods made from plants
What is a flexitarian diet?
A predominantly vegetarian diet but meat is occasionally consumed.
What are some advantages of vegetarian diets?
- Lower levels of saturated fats
- Lower consumption of added sugar
- Low or no consumption of cholesterol
- High intake of fiber, magnesium, potassium, folate, antioxidants, and phytochemicals
- Lower reported BMI
- Lower odds of mortality from heart disease
What are some disadvantages of vegetarian diets?
- Risk of vitamin B12 deficiency
- Inadequate vitamin D consumption if no dairy is consumed
- Difficulty in consuming adequate calories
- High risk of iron deficiency anemia
- Risk of protein deficiencies
True or False: A vegetarian diet can lead to lower blood pressure.
True
Are plant based diets typically associated with weight loss?
Yes, can be associated with weight loss because typically less dense calorically than other foods (feel fuller sooner due to volume).
What is the typical fat intake percentage for low-fat diets?
<30% of energy intake from fat.
What is the potential effectiveness of low-fat diets?
May lead to weight loss due to reduced energy density and lower caloric intake.
Studies show that populations with lower ___ intake have less obesity.
Fat
Is there a recommended limit for cholesterol intake?
No, the recommended limit has recently been removed, but with a new emphesis on eating less CHO as they tend to be high in saturated fats.
What is a VLCK diet?
Very Low CHO Ketogenic diet: <30g CHO per day, will usually permit ketosis to occur.
What are the different types of low carb diets?
Reduced carbohydrate diet: >130g of carbohydrate per day, up to 45% of total calories
Low carbohydrate diet: 30-130g of carbohydrate per day OR less than 20g/day for 2 weeks then <50g/day
What is the purpose of low carbohydrate diets?
Promotes adipose tissue metabolism when carbohydrates are absent.
What is the function of ketones?
Produced when burning fat (ie. Not enough CHO); interacts with incretine hormones (CCK/ghrelin) to suppress appetite.
Some studies claim that ketones are not related to weight loss (NEJM Study) but evidence of the correlation is clear.
Low carb diets cause rapid weight loss due to…
Appetite suppression and water loss (1-2kg in 7-14 days)
Why would low carb diets not work?
- Too restrictive
- Unlikely to be adhered long-term
- Concerns with high meat consumption
- Discouraging after initial success slows down
- Potential for nutritional inadequacies?
- Potential interference with higher amounts of training?
Explain the results of Nordmann (2006).
Found that low CHO diets were better for HDL and TG, while low fat diets were better for LDL and total CHO.
Seen in some adherence studies, where improvments in HDL were seen at 2 years.
In some studies, people with high insulin response to 75g OGTT lost more weight on a low ___ diet.
Low CHO diet.
What are the pros and cons of a high protein diet?
Pros:
* High satiety
* Energy demanding to store excess protein
* Can taste good
* Preserve fat free mass
Cons:
* Concerns with high meat consumption
* Potentially costly
What evidence supports a high protein diet?
Studies found that high protein diets may be helpful for prevention. Individuals lost 8% of BW through a low calorie diet, then utilized a high protein diet for prevention.
Evidence is not consistent to date
* Effect on FFM is small
* May require resistance training
* FFM is not the same as muscle mass!
What are some risks associated with high protein diets?
- Safety issues with some protein supplements
- Excess protein can be hard on the kidneys
- Health issues with high meat consumption
Often similar to low carbohydrates.
What are the health issues that can arise from high levels of meat consumption?
Cooking temperature…high temperature cooking produces carcinogens.
Haem Iron… (found in red meat and is easy to absorb; non-haem is vegetable based proteins)
- “17% increased risk per 100 g per day of red meat”
- “18% increase per 50 g per day of processed meat”
What is a very low-calorie diet (VLCD)?
A diet that typically provides 400-800 kcal/day, often used for weight loss.
1920s: 400 kcal/day
More recently: <800 kcal OR <50% of RMR
What are some potential negative side effects of low-fat diets?
- Low palatability
- Possible deficiencies in essential fatty acids and fat-soluble vitamins
Who are VLCDs for?
- BMI > 30 kg/m2 at risk of diabetes/CVD
- No medical and behavioral contraindications
- Non pregnant
- People who have money (expensive)
- Not everybody can adhere…
VLCDs occurred in the 1970s when dieters consumed products that contained low-quality protein (i.e., hydrolyzed collagen) and were deficient in vitamins and minerals.
Canadian guidelines do not talk about VLCD
True or False: Low carbohydrate diets have been shown to lead to similar weight loss as low-fat diets in long-term studies.
True
Why do VLCDs work?
- “Simple” to follow
- No food preparation
- No calorie counting
- Large energy deficit
- Rapid weight loss can be motivating
- Could be a starting point to other changes (ie. exercise).
- Help break eating habits or “addictions”?
BUT not a long term solution and people often return to old behaviours after VLCDs. Must also be medically supervised.
What is the evidence supporting VLCDs?
Rapid weight loss.
15% to 25% of initial weight in 3 to 4 months
Long term weight loss <,=, or > LCD
BUT can cause gallstones, cold intolerance, hair loss, headaches, fatigue… etc.
What is the recommendation for adults living with obesity and type 2 diabetes regarding weight loss?
Consider intensive lifestyle interventions that target a 7%-15% weight loss.
What are crash or fad diets?
Diet plans which involve making
extreme, rapid changes to food consumption.
Often very low in calories, deficient in nutrients, unsustainable.
Think… Cabbage soup diet, Grapefruit Diet, Master Cleanse Diet, Fat flush diet
What is the suggested approach for improving quality of life in adults living with obesity?
A nondieting approach to improve psychological outcomes, cardiovascular outcomes, and eating behaviors.
Do macronutrient diets work?
Most macronutrient diets, over six months, resulted in modest weight loss and improved blood pressure. At 12 months, weight reduction diminished, and blood pressure improvements largely disappeared.
Fill in the blank: Adults living with obesity should receive individualized medical nutrition therapy provided by a _______.
[registered dietitian]
What is the goal of intensive behavioral interventions for adults living with obesity?
To target a 5%-7% weight loss to improve glycemic control and reduce the incidence of type 2 diabetes.
What are the impacts of low carbohydrate diets on appetite?
Ketogenic diets are associated with suppressed appetite, but the role of ketones in appetite reduction is less clear.
What is the increased risk associated with red meat consumption?
17% increased risk per 100 g per day of red meat
Indicates a correlation between red meat intake and health risks.
What is the increased risk associated with processed meat consumption?
18% increase per 50 g per day of processed meat
Highlights the health implications of processed meat consumption.
What are Very Low Calorie Diets (VLCD)?
Diets defined as < 800 kcal or <50% of RMR
Originally studied for their impact on weight loss and starvation.
What were the calorie restrictions in VLCDs in the 1920s?
400 kcal/d with 1g protein/kg ideal weight
Early VLCDs led to significant weight loss but also to lean tissue and mineral losses.
What is an example of a VLCD product and its composition?
Optifast: 300 kcal/d in 5 feedings (45 g protein, 30 g CHO, 2 g essential fatty acids)
Designed to provide essential nutrients while restricting calories.
Who are VLCDs intended for?
Individuals with BMI > 30 kg/m2 at risk of diabetes/CVD, no contraindications, and non-pregnant
Indicates specific criteria for VLCD eligibility.
Why might VLCDs be considered effective?
Simple to follow, no food preparation, large energy deficit, rapid weight loss
Can serve as a motivator for behavioral changes.
What are some reasons VLCDs might not work long-term?
Not a long-term solution, costly, must be medically supervised, behavior changes not guaranteed
Emphasizes the challenges of maintaining weight loss after VLCD.
What is the evidence regarding weight loss from VLCDs?
Patients can lose 15% to 25% of initial weight in 3 to 4 months, but regain 40% to 50% after 1 to 2 years
Suggests that without follow-up care, weight regain is common.
What are potential negative side effects of VLCDs?
Gallstones, cold intolerance, hair loss, headache, fatigue, dizziness, muscle cramps
Indicates health risks associated with VLCDs.
What characterizes crash or fad diets?
Extreme, rapid changes to food consumption, often <1000 kcal/day
Examples include the Cabbage Soup Diet and Master Cleanse Diet.
What is the Master Cleanse Diet?
A liquid diet for 3-10 days, created in 1941, with calories ranging from 600-1200 kcal/day
Initially designed for ulcer treatment but popularized for detoxification.
What is the effectiveness of popular diets like Atkins and Weight Watchers according to Dansinger 2005?
Adherence rates were similar and weight loss was minimal across diets
Highlights the importance of adherence in diet effectiveness.
What is a key factor affecting the effectiveness of diets?
Adherence
Consistent commitment to the diet is crucial for weight loss success.
What general conclusion can be drawn about diets causing weight loss?
All diets that cause weight/fat loss reduce energy intake
The more foods are restricted, the more energy intake decreases.
What factors can influence individual responses to diets?
Palatability, hunger, physiology, behavioral/socio/cultural issues, genetics
Personal preferences and biological factors can affect diet adherence and success.
What should be considered when choosing a diet?
Risk-benefit ratio and long-term sustainability
Important for maintaining health and achieving weight loss goals.
Why would low fat diets work?
Efficiency of storing fat as fat
Low thermic effect of feeding of fat
Taste/texture
Fat has low Satiety
Why would low fat diets work?
Palatability
High CHO/sugar content
Evidence that fat intake ↓ while obesity rates ↑
Fat can have high satiety… May depend on:
* Amount of fat
* Fatty acid chain length (medium chain are more satiating than long chain)
* Degree of Saturation (more saturated = more satiety)
* What it is eaten with (Fiber, CHO, Sugar)
When are low fat diets preferred?
For metabolic reasons, to discourage overcomsumption (high fat foods have weak satiety), to help with or maintain weight loss, for heart health and certain cancers.
What are the negative effects of low fat diets?
Low palatibility, may be better for prevention rather than weight loss, adequate comsumption of essential FA/ lipo-soluble vitemins/ HDL?
