NUTRITION wk 1-6 Flashcards
what is NAFLD ultimately
ultimately a disorder of dysregulated fuel storage (too much fuel, or not spending enough)
what can NAFLD progress to
cirrhosis or hepatocellular carcinoma
Once liver inflammation and liver damage begin a diagnosis of Non- Alcoholic Steatohepatitis (NASH) is made
what are the three monosaccharides of carbohydrates
glucose
fructose
galactose
three disaccharides of carbs
- Sucrose (glucose + fructose) - Lactose (glucose + galactose) - Maltose (glucose + glucose)
what is glucose
The common body fuel for oxidation and found in blood and tissue fluids and metabolized in most body tissues
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Most complex carbohydrates are digested into units of glucose or converted to glucose for fuel
what is galactose
it is a monosaccharide
Not found as a monosaccharide in foods but rather bound to glucose to form the disaccharide lactose
Converted to glucose in the liver to be used as fuel through a reversible process
Glucose converted to galactose during lactation
Galactose is a common constituent in glycolipids and glycoproteins
Dietary sources include anything with lactose (dairy foods, etc.)
what is fructose
The sweetest of simple sugars
Converted to glucose in the liver and intestine
Transport and metabolism of fructose does not require insulin
Only a few tissues have the capacity to metabolize it (liver, intestine, kidney, adipose and muscle tissue)
Since so few tissues can metabolize it directly, the vast majority is metabolized in the liver
Usually ends up replacing liver glycogen or being used in the synthesis of triglycerides
how is the majority of fructose absorbed
The majority of ingested fructose is passively absorbed by GLUT5 transporters
High fructose diets can amplify absorption by upregulating additional transport mechanisms
what happens if too much fructose
Processing of fructose in the liver is not controlled by hormone or allosteric mechanisms (there is no rate- limiting step like there is with glycolysis)
Metabolic changes do not act as feedback inhibitors as they do with glycolysis
Excess metabolites (like pyruvate) enter various other pathways such as fatty acid synthesis and cholesterol
dietary sources of fructose
Naturally found in fruit and some vegetables, honey, agave nectar/syrup
High-fructose corn syrup (HFCS)
- Sugar-sweetened beverages
- Processed foods
- “Added” sugar
what are complex carbs
Polysaccharides – longer chains of glucose units
Oligosaccharides – smaller chains of 3 – 10 glucose units
Physiologically relevant polysaccharides:
- Starch is the storage form of carbohydrates in plants
- Glycogen is the storage form of carbohydrates in animals
therapetucitc considerations for NAFLD in diet
no alcohol
mindful of medications harming liver
risk factors- obesity, hypertension, diabetes
basic therapies for NAFLD and obesity
- Avoiding excess sugar/carbohydrate consumption, especially fructose
- Reducing saturated/trans fat intake
- Opting for lean proteins and increasing vegetable consumption
- EXERCISE
best diet for NAFLD
mediterranean diet
lower carb
what is recommended in Mediterranean diet
olive oil, nuts, fruit, veg, fish, sofrito, legumes, white meat, wine
storage from of glucose in plants
starch
storage form of glucose in anaimals
glycogen
Which of the following dietary recommendations is consistent with the Mediterranean diet?
A. Three servings or more of red meat per week B. Three or more servings of legumes per week
C. One daily serving of white wine
D. Less than four tablespoons of olive oil per week
B
risk factors for T2d
Genetics
Obesity
Age
History of gestational diabetes Sedentary lifestyle
Tobacco smoking
prediabetic range for HbA1c
5.7-6.4
how much of HbA1c reductions can be achieved by nutrition therapy
1-2%
what ethnocultural factors to take into account when giving nutritional recommednations
- cultural foods
- dining habits
- lifestyles
- food preparation techniques
- avoided foods and cultural eating practices (fasting, feasting, etc.)
weight loss in T2D to improve glycemic control, insulin sensitivity and reduce hypertension and dyslipidemai
Even weight loss of 5 – 10% of initial body weight can improve glycemic control, insulin sensitivity, reduce hypertension and dyslipidemia
meal timing and taking insulin
More important for people with T1D or those with T2D taking insulin
Insulin dosing generally needs to be adjusted for periods of fasting
Intermittent fasting can be helpful but requires close monitoring and is generally difficult to do
when to eat carbs if taking insulin or have diabetes
spread throughout the day
macronutrient breakdown for diabetes
General recommendation of 45 – 60% carbohydrates, 10 – 35% protein, 20 – 35% fat
what happens if reduce carbs below 45%
Reducing carbohydrate intake below this threshold tends to result in an increased consumption of saturated fats
what is the glycemic index
- an assessment of the quality of carbohydrate-containing foods based on their ability to raise blood glucose
low vs medium vs high glycemic index foods
Low GI foods have a score of 55 or less
Medium GI foods score between 56 and 69
High GI foods have a score of 70 or more
what is a low glycemic index similar to
high fibre diet
dietary fiber good for diabetes how
Evidence is greatest for viscous soluble fibres from different plant sources as they slow gastric emptying and delay the absorption of glucose in the small intestine
Examples: beta-glucan from oats and barley, mucilage from psyllium, glucomannan from konjac mannan, pectin from dietary pulses, eggplant, okra, and temperate climate fruits (apples, citrus fruits, berries, etc.).
added sugars and diabetes
Limit or eliminate, especially fructose-containing sugars
Limit or eliminate sugar sweetened beverages especially if they account for more than 10% of total daily energy
which type of sugar is worse
fructose
fats recommednations for diabetes
General focus on replacing saturated fats from meat with polyunsaturated fatty acids (PUFAs)
Quality of fat has been shown to be more important than quantity
protein recommendation for kg of body weight
0.8 g per kg body weight recommended
Usual intake is 1 – 1.5 g per kg body weight representing 15 – 20% of total energy intake
when is protein consumption increase recommended
Increase in protein consumption generally recommended with energy-reduced diets unless patient has chronic kidney disease
mediterranean diet for diabetes
the best dietary approach to prevent cardiovascular disease and improve glycemic control
Can be modified to account for individual needs (reduced carbohydrate intake, exclusion of alcohol, etc.)
DASH diet
Dietary Approaches to Stop Hypertension
Good option when the patient is already hypertensive
goal of DASH diet
General goal is to reduce sodium and increase potassium intake through dietary emphasis on vegetables, fruits, and low-fat dairy products, and includes whole grains, poultry, fish, and nuts.
Smaller amounts of red and processed meat, sweets, sugar-containing beverages, total and saturated fat, and cholesterol, and larger amounts of potassium, calcium, magnesium, dietary fibre, and protein than typical Western diets
dash and low sodium diet effect on diabetes
Some evidence to suggest improvements to glycemic control
Much more evidence specifically for reducing blood pressure
Possible increased mortality risk if sodium intake is below 1500 mg per day
what is the lowest to go with sodium
1500mg /day
Possible increased mortality risk if sodium intake is below 1500 mg per day
ketogenic diet
Good option for improving glycemic control and facilitating weight loss
Difficult for long term engagement
No evidence that it improves mortality with T2D
Conflicting evidence with whether or not it reduces cardiovascular risk
Which of the following dietary recommendations is the safest and most effective for improving glycemic control in a patient with type 2 diabetes requiring insulin?
A. Engage in intermittent fasting with an 8-hour eating window
B. Follow a ketogenic diet
C. Follow a moderate-carbohydrate diet with regular meal timing
D. Follow a low sodium diet consuming no more than 1000 mg per day
C. Follow a moderate-carbohydrate diet with regular meal timing
RDA for iodine
RDA is 150 mcg/day or most adults
RDA increases to 220 mcg/day during pregnancy and 290 mcg/day during lactation
good food sources of iodine
Seafood
Sea vegetables (kelp, seaweed, etc.)
Iodized salt (1 mg of iodine per 10 mg salt)
Calcium and potassium iodide food additives in commercially produced bread
Toxicity results from intakes of several grams
minerals for hypothryoid
zinc
iodine
copper
manganese
chromium
seleniun
flouride
where is iodine stored? excreted? form
thyroxine in thyroid
excrete in urine
metabolism by liver and excrete in bile
what enzymes is zinc a part of in the body
zinc metalloenzymes
when is zinc important in body
Vital throughout life but particularly important during periods of growth
Involved in protein, DNA, and RNA metabolism
where is zinc absorbed? what affects absorption?
SI
Rates of absorption are dependent on body status (low zinc levels = higher percentage of zinc absorbed)
Absorption inhibited by alcohol consumption
where is zinc stored
muscle and bone
what is RDA for zinc
RDA is 11 mg for men and 8 mg for women but is ultimately dependent on body size
what does zinc interfere with
Supplementation can result in copper deficiency
Interferes with iron absorption
food sources of zinc
Seafood (oysters highest)
Meat, eggs, milk
Legumes and whole grains
Animal sources have higher bioavailability than plant sources
what can deplete copper
zinc supplementation
what is RDA for copper
900 mcg/day
food sources of copper
Food sources include: seafood (oysters), nuts, seeds
Possible leeching with uncoated copper cookware
what is manganese do in the body
Cofactor for many enzymes (e.g. superoxide dismutase)
Involved in amino acid, cholesterol, glucose, and carbohydrate metabolism; reactive oxygen species scavenging; bone formation; reproduction; and immune responses
Also plays a role in blood clotting and hemostasis in conjunction with vitamin K
when would manganese deficiency occur
Deficiency uncommon but may occur with pancreatic insufficiency
where does manganese accumulate and what can It cause
Excess accumulates in the liver and CNS leading to psychiatric disturbances and neuromuscular symptoms
Toxicity is usually the result of environmental exposure
what is adequate intake of manganese
AI is 2.3 mg/day in men and 1.8 mg/day in women
Typical diet supplies 1.6 mg/1000 kcal
food sources of manganese
Grains
Legumes
Nuts and seeds
Leafy vegetables
Coffee and tea
how does chromium effect insulin
Part of a protein complex that potentiates insulin activity and assists with moving glucose into cells
what is adequate intake of chromium
AI is 35 mcg/day in men and 25 mcg/day in women
AIs go down after age 50
what are food sources of chromium
brewer’s yeast, liver, cheddar cheese, wheat germ and whole grains
where is selenium found in the body
Deposited in all body tissues except adipose tissue
Concentrations highest in liver, heart, kidney, and spleen
what is selenium part of
Integral to selenoproteins like glutathione peroxidase and deiodinase, among many others
Glutathione peroxidase works in conjunction with vitamin E
what is RDA for selenium in normal people vs hypothyroid
RDA is 55 mcg/day for all adults
Supplementation within the context of hypothyroidism is usually around 200 mcg/day
food sources of selenium
Brazil nuts (68 – 91 mcg per nut)
Seafood
Legumes
Whole grains
Lean meats Dairy products
where does fluoride accumulate
Accumulates in calcified tissues
Important during growth of calcified tissues where incorporation of fluoride results in resistance to resorption
Fluoride-containing crystals are more resistant to bacterial acids
adequate intake of flurodie? excessive intake? toxic?
AI is 4 mg/day for men and 3 mg/day in women
Excessive intake leads to pitted and discoloured teeth
Toxicity is usually associated with intakes of 10 mg/day or more for 10 years or more
food sources of fluoride
Fish and fish products
Tea
Consumption of fluoridated dental products
Fluoridated water supplies
what calorie considerations in hypothryoid
Metabolic rates for people with hypothyroidism are slower, especially in untreated patients
Energy needs can be 15 – 40% lower
Weight gain is common and significant changes in fluid retention can occur
Assess caloric intake and adjust as necessary
nutrient consideration in hypothyroid
Ensure iodine and selenium intake are sufficient
Incorporate iodine and selenium-rich foods
Possible supplementation
Avoid excessive iodine intake in those already medicated
what are goitrogens
Compounds that interfere with thyroid hormone production
Usually exert their effect after prolonged use and have a greater effect with iodine intakes are low
Many are naturally occurring: thiocyanates, glucosinolates, some flavonoids
food examples of goitrogens
Cassava, lima beans, linseed, sorghum, and sweet potato contain cyanogenic glycosides that are metabolized to thiocyanates that compete with iodine for uptake in the thyroid
Soy and millet contain flavonoids that impair thyroid peroxidase activity
Cruciferous vegetables contain glucosinolates and their metabolites compete with iodine for thyroidal uptake
what are 3 goitrogens
- thiocynates
- glucosinolates
- flavonoids
how to reduce goitrogens
cook it and eat iodine
Food sources are generally considered healthy and should not specifically be avoided
Most goitrogens are reduced by cooking the food sources
Ensuring iodine intake is sufficient helps offset any effect
vitamin A for hypothryoid
Appropriate thyroid function is needed for vitamin A metabolism
Lower body level of vitamin A is possible in those with hypothyroidism
Consider food sources of carotenoids
Which of the following trace minerals are directly involved in thyroid metabolism and function?
A. Chromium and zinc
B. Zinc and iodine
C. Iodine and selenium
D. Selenium and chromium
C. Iodine and selenium
