CV Nutrition Flashcards
Describe the influence of saturated fats on serum lipids and the general dietary guidelines
o Primary dietary influence on serum cholesterol levels
• Suppress synthesis of LDL receptors
• Less LDL clearance
o 1% kcal consumed as saturated fat increases serum cholesterol by 1.8 mg/dL
o Genetic variation in response
Recommend: <7% of calories (16 g/d for 2000 calories)
Describe the influence of dietary cholesterol on serum lipids and the general dietary guidelines
o Influence is more variable than influence of saturated fat, so limiting saturated fats is prioritized over cholesterol
o Can raise concentrations of all lipoproteins
o Raises LDL-C by suppressing LDL receptor synthesis in liver
o About ½ amount eaten is absorbed each day
Recommend: goal for lipid management <200 mg/d
o Use low-fat dairy, smaller amounts of lean meat, no more than 4 eggs yolks/week, limit liver to 1/month, shrimp to 1/week
Describe the influence of trans fats on serum lipids and the general dietary guidelines
o Formed from hydrogenated vegetable oils
o Raise LDL-C,
o May decrease HDL-C, raise Lipoprotein(a) and increase levels of inflammation
o Goal to reduce intake to <1% calories
Describe the influence of unsaturated fats on serum lipids and the general dietary guidelines
o Goal: 15-25% total calories
o Reduce LDL-C, no reduction in HDL-C
Monounsaturated
• Olive and canola oil, nuts, avocado
Polyunsaturated
• Omega-3 (alpha-linolenic acid)
• Fish, flax seeds, soybean, walnuts, canola oil
• Reduce platelet aggregation
• Anti-inflammatory
• Anti-arrhythmic effects
• WHO recommendation: 0.3-0.5 g/day of EPA and DHA
• AHA recommendation: 1 g/day for people with CHD
• 3-4 g/day to reduce TG
• Omega-6 (linoleic acid)
• Corn, safflower, sunflower, and cottonseed oils
Describe the influence of dietary fiber on serum lipids and the general dietary guidelines
Soluble/viscous
• Recommended intake: 10-25 g/d
• Delays gastric emptying, slows glucose absorption, decreases blood cholesterol, increased fecal excretion of bile acids
• Reduces LDL-C and blood sugar levels
Insoluble fiber
• Increases fecal bulk, decrease intestinal transit time
• Does not lower cholesterol, but benefits GI
Total fiber
• Recommended intake: 20-30 g/d
Supplements
• Psyllium: >10 g/d
• Metamucil: has 3.6 g psyllium
• Increases bile acid excretion, may reduce cholesterol absorption, fermentation byproducts may reduce cholesterol synthesis
Describe the influence of soy products on serum lipids and the general dietary guidelines
o Can reduce cholesterol by stimulating LDL-receptor production
o Safe, though may interfere with thyroid medication absorption
Describe the influence of phytosterols on serum lipids and the general dietary guidelines
o Found in small amounts in plant foods (soy, beans, whole grains)
o Interfere with cholesterol absorption in gut
o 2 tbsp/d spread gives 2 g plant sterols → reduces LDL-C 5-15%
Describe the influence of excess calories on serum lipids and the general dietary guidelines
o Enhanced production of VLDL → higher TGs
Describe the influence of alcohol on serum lipids and the general dietary guidelines
o Increases liver TG production and VLDL
o More pronounced in people who drink large amounts of alcohol, are obese, have diabetes, have a TG disorder
Describe the influence of carbohydrates on serum lipids and the general dietary guidelines
o Can raise TG, which can lead to decreased HDL
o Refined CHO have most dramatic effect
o CHO → glucose → fatty acids → TG
o Fructose has greater TG increasing effect
o Goal: 60% calories or less to control TG
Compare and contrast the National Cholesterol Education Program Step One Diet, the TLC diet, very low fat diets and the Mediterranean diet.
Step One Diet
o For general public
TLC: therapeutic lifestyle changes
o For people with diagnosis of heart disease, diabetes or lipid abnormalities (For high LDL, metabolic syndrome, or low HDL)
o Lower in saturated fat and cholesterol than Step One diet for general public
o Can be enhanced with adding fiber supplements or plant sterols
o Encourages regular exercise
Very low fat diet o Versions: Pritikin, Ornish, Esselstyn o Fat 500mg/dL o Decreases LDL-C; likely to increase TG and decrease HDL since more CHO o effective for weight loss
Mediterranean diet
o 30-40% diet from fat (saturated fats <7%)
o Emphasis on monounsaturated fat, omega-3 fats, limited saturated fats
o Reduced risk of heart disease by 30%
Diet recommendations for low HDL
o Small increases from weight management and physical activity
o Very low fat diets usually decrease HDL
o Reducing elevated TG usually leads to increased HDL
o TLC and Mediterranean most appropriate recommendation
Diet recommendations for hypertriglyceridemia
o Very low fat diet (10-15% calories)
o Reduces production of CMs
o May add medium chain triglycerides to increase calories and palatability because do not contribute to CMs
List the categories of people for whom the lowest sodium intake (1500 mg sodium per day) is recommended.
o Female gender o Advanced age o Abdominal obesity o African-American race o Higher levels BP o Impaired glucose tolerance o Diabetes o Family history of HT
Outline recommended dietary changes for a low sodium diet.
For healthy people: 2300 mg/d with a gradual reduction to 1500 mg/d
o Since high sodium diets increase risk of stroke, left ventricular hypertrophy, osteoporosis, kidney stones, possible gastric cancer
o Guidelines: use half amount salt in recipes, add no salt at table, limit use of high sodium processed foods, eat out less often
o Salt substitutes ok unless serum K+ high
For people with HT, anyone over 50, all African-Americans: 1500 mg/d
