Chaper 7 2/2 Flashcards
Energy Balance: Feasting
While feasting metabolism favours fat formation, fat cells enlarge whether its from protein, carbs or fat
-most efficient when it comes from dietary fat
-during digestion, tryglicerides are broken down absorbed and put back together for storage
-Carbs must become pyruvate then acetyl CoA and then assembled into triglycerides
Energy balance: fasting
During starvation the body will conserve more energy so there is enough to run critical functions
-It suppresses the desire to search for food and by slowing all metabolic functions
- this means reducing energy output and conserving fat and lean tissue will still shrink, but will preform less work
-The need for glucose poses a major problem, the body can use its stores of fat to furnish most of its cells with energy, but the red blood cells are completely dependant on glucose, and the brain and nerves prefer energy in the form of glucose
Fasting and weight loss
starvation reduces weight but not just fat loss
wasting,, reduced heart rate and reduced resistance to disease
depression, anxiety, intense focus on food, body can live up to two months like this
Fasting beyond glycogen depletion
as the stores of liver glycogen are used up, muscles and other body proteins can be broken down to synthesize glucose
not energy efficient but has to be done to keep glucose to the brain and nervous system -fatty acids can be used by tissues for energy and glycerol can go to the liver to be converted to glucose
-if fasting persist the body adapts by combining acetyl coa fraagments to produce keton bodies which is the alt source of fuel for the nervous system and the brain
- can use ketones for an extended period of time; however, there is a danger of developing ketosis
-ketosis results from inc levels of keto acids in the blood which in turn lowers the pH of the blood
Intermittent Fasting
unlike prolonged fasting, it can be done in a way that sustains nutrient use and good health
-choose to fat sometimes
-zimproves GI microbiome, inflammation, sleep, blood lipids, blood glucose and insulin response
not appropriate for everyone, children, pregnant people, people with diabetes on insulin or. medication, hypoglycemia and eating disorders
Keto diets
mimic the metabolism that occurs during fasting
results in rapid weight loss initially, due to losses in glycogen and protein together with a large quantities of body fluids
-weight loss not usually sustained long-term and is comparable to what is seen from other weight loss diets
unpleasant side effects
long term effects not known
alcohol in the body
Some studies have shown that moderate alcohol consumption may decrease mortality, inflammation and risk of heart disease in older adults
- for younger people its a leading factor of premature death and disability
-no amount of alcohol improves health, no one should begin to drink alcohol or purposefully continue to drink alcohol for health reasons
-drinking alcohol is not a disease prevention strategy any benefits of moderate alcohol use are outweighed by the many potential harmful effects of excessive alcohol use
Canada’s low-risk drinking guidelines
-Continuum of risk
-completely avoid in some individuals: pregnant, breastfeeding, taking certain medications or with some medical conditions, people working, driving or alcoholics
women -no more than 2 drinks a day and 10 drinks a week
men no more than 3 drinks/day or 15 drinks/week (some days with no alcohol consumption
Alcohols influence on the GI Tract
Empty stomach vs full stomach , takes longer for alcohol to reach the brain on a full stomach
-broken down by dehydrogenase enzyme
-rapid absorption in the small intestine
-alcohol cannot be stored in the body and is potentially toxic
alcohols influence on the liver
-1st to receive alcohol laden blood
- primary site of alcohol metabolism, liver has to process it at the expense of preforming other functions
-alcohol dehydrogenase is the enzyme that breaks down alcohol bi product is acetaldehyde which is highly toxic
-the alcohol circulated through the body until the liver has time to process it
-H+ ions accumulate and shift the body’s acid base balance toward acid d
-H+ and coenzymes build up , which slows the TCA cycle
-pyruvate abd acetyl coa build up, the excess acetyl coa takes an alt pathway toward fatty acid synthesis
-fat clogs the liver
alcohol in the body
1)judgement and reasoning
2)speech and vision
3)voluntary muscular control
4)respiration and heart action
Other damage done by alcohol
Dehydration
malnutrition
Alcohol and weight
Moderate drinkers with stimulates appetite = weight gain
heavy drinkers, nutrient deficiencies as alcohol replaces food intake
Wernicke korsakoff syndrome - thyamine deficiency affects nerve and muscle function
