Cardiovascular Disease and Nutrition: Dietary Fats, Blood Lipids, and Prevention

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Cardiovascular Disease (CVD)

Definition and Overview

Cardiovascular disease (CVD) refers to dysfunction of the heart and blood vessels. The type and amount of dietary fat consumed can contribute to or protect against CVD. CVD is an umbrella term that includes coronary heart disease, stroke, and hypertension. - Coronary Heart Disease: Blockage of blood vessels supplying the heart, leading to reduced blood, nutrients, and oxygen flow, which may cause heart attacks. - Stroke: Blockage or rupture of blood vessels supplying the brain, resulting in loss of function such as movement or speech. - Hypertension: High blood pressure, often asymptomatic, increases risk for heart attack or stroke. Heart and ECG line

CVD Statistics

Heart disease is the leading cause of death for both men and women in the U.S., regardless of ethnicity. - ~695,000 Americans died from heart disease in 2021 (1 in every 5 deaths). - CVD costs the U.S. nearly $240 billion annually. Heart Disease Death Rates Map

Symptoms of Heart Attack and Stroke

Symptoms can differ between men and women. - Heart Attack: Men often experience chest pain, while women may have nausea, jaw pain, or fatigue. - Stroke: Both genders may have face drooping and speech difficulty, but women can also experience headaches and fatigue. Heart Attack Symptoms: Men vs. Women Stroke Symptoms: Women vs. Men

Risk Factors for CVD

Non-Modifiable Risk Factors

- Age (Men > 55 years, Women > 65 years) - Male gender - Family history - High-risk ethnicity (e.g., South Asian ancestry)

Modifiable Risk Factors

- Visceral adipose tissue - Sedentary lifestyle - Smoking and secondhand smoke exposure - Abnormal blood lipids - Hypertension - Diabetes - Inflammation - Air pollution

Atherosclerosis

Pathophysiology

Atherosclerosis is the buildup of lipids and scar tissue (plaque) in arterial walls, impairing blood flow and increasing risk of CVD. - Process: Endothelial injury → immune response → inflammation → increased permeability → cholesterol entry → plaque formation → narrowed artery/risk of rupture. - Causes: Hypertension, irritants (nicotine, tobacco, high blood glucose), bacteria, viruses. - Plaque Contents: Lipids, immune debris, clotting material. Atherosclerosis and cardiovascular disease

Blood Lipids and CVD

Types of Blood Lipids

Blood lipids include triglycerides, cholesterol, chylomicrons, VLDL, LDL, and HDL. - LDL (Low-Density Lipoprotein): High levels increase CVD risk. - HDL (High-Density Lipoprotein): High levels decrease CVD risk. - Triglycerides: High levels increase CVD risk. Blood lipid types and functions

Blood Lipid Values and Interpretation

Blood lipid values are used to assess CVD risk.

Type	Optimal	Moderate	High
Total/HDL ratio (Men)	<3.5	3.5–5.0	>5.0
Total/HDL ratio (Women)	<3.0	3.0–4.4	>4.4
LDL to HDL ratio	<2.5	2.5–3.3	>3.3
HDL to LDL ratio	>0.4	0.4–0.3	<0.3
TG to HDL ratio	<2	2–3.8	>3.8

Fasting Blood Cholesterol Profile Table Blood lipid ratio table

LDL Receptor Activity

Diets high in saturated and trans fats reduce LDL receptor activity, leading to elevated LDL levels in the bloodstream and increased plaque formation. LDL receptor activity diagram

Dietary Fats and CVD Risk

Saturated and Trans Fats

- Saturated Fats: Increase LDL cholesterol, reduce LDL receptor activity, promote plaque formation. - Trans Fats: Increase LDL, decrease HDL, raise inflammation and heart attack risk. Change in CHD risk by fat type

Role of Sugar

High sugar intake, especially fructose, increases LDL, reduces LDL particle size, raises triglycerides, lowers HDL, and promotes atherosclerosis. Fructose increases LDL meta-analysis High disaccharide intake and lipoprotein profile

Dietary Treatment and Prevention

Dietary Recommendations

- Limit refined carbohydrates, saturated fat, and alcohol. - Increase omega-3 fatty acids, niacin, and physical activity. - Total fat intake: 20–35% of total calories. - Saturated fat: <10% (DGA), <6% (AHA) of total calories. - Trans fat: reduce to absolute minimum. - Increase dietary fiber (20–35 g/day), fruits, and vegetables. - Folate: 400 mcg/day to lower homocysteine. - Decrease salt, increase potassium. Omega-3 rich foods Omega-3 fatty acid content table EPA-DHA supplement Omega-3 production process Salmon and vegetables Nuts

DASH Diet

The Dietary Approaches to Stop Hypertension (DASH) diet emphasizes whole grains, fruits, vegetables, nuts, seeds, and limits red and processed meats. DASH diet diagram

Red and Processed Meat

- 100g red meat/day does not significantly increase CHD risk. - 50g processed meat/day increases CHD risk. Red meat and CHD risk Processed meat and CHD risk

Lifestyle Changes for CVD Prevention

Recommendations

- Limit alcohol (<2 drinks/day for men, <1 for women). - Manage stress and get adequate sleep (at least 7 hours/night). - Maintain normal blood glucose. - Stop smoking/tobacco use (reduces risk by 50% within one year). - Regular health screenings. - Maintain active lifestyle and healthy body weight. Sleep and CVD mortality

Summary: Fat & CVD Mortality

Key Takeaways

- Dairy products with saturated fat: neutral effect on mortality. - Nuts, olives, olive oil: decrease mortality. - Replacing saturated fat with mono/polyunsaturated fats: decreases mortality. - Replacing saturated fat with refined carbs: increases mortality. - Good eating patterns containing fat are acceptable when balanced and healthful. Isocaloric substitution and CVD risk Salmon fillets Additional info: The notes expand on the original content by providing definitions, dietary recommendations, and context for interpreting blood lipid values and lifestyle modifications for CVD prevention.