CARDIOVASCULAR HEALTH

CARDIOVASCULAR HEALTH

Blood is circulated in our body by a vast network of blood vessels. These range from the tiniest, one-blood-cell-wide capillaries to the largest arteries keeping our organs well supplied with oxygen and other nutrients. And, of course, the organ keeping everything going is our muscular heart, which pumps about 2,000 gallons of blood per day!

Broadly speaking, cardiovascular disease (CVD) occurs when:

• Inflamed fatty plaques build up in blood vessels.

• Vessels become stiff and constricted, potentially even blocked.

• Blood becomes more likely to coagulate, or clot.

Optimal cardiovascular health thus means:

• Keeping our heart strong.

• Helping our blood vessels stay strong and elastic (to support the pressure of the fluid flowing through them).

• Keeping vessels' lining, or endothelium, smooth and well repaired to reduce the risk of plaque build-ups and inflammation within the vessels that can block fluid moving through.

• Decreasing systemic inflamation (which can affect the health of blood vessels) and factors that increase abnormal blood clotting.

KEY NUTRITION SKILLS

CVD (heart disease and stroke) is one of the biggest chronic disease risks after menopause, as women lose the cardioprotective effects of estrogens. In part, this is due to the effects of changing sex hormone levels on:

• The metabolism of lipids (fats)

• Triglycerides (the storage and transport form of fatty acids)

• Cholesterol

• Lipoproteins (proteins - such as low-density lipoprotein [LDL] and high-density lipoprotein [HDL] - that carry particular types of fatty particles, including cholesterol, around the body).

• Systemic inflammation

Key nutrition behaviors for cardiovascular health include:

EATING MORE MINIMALLY PROCESSED FOODS

Whole foods (especially colorful fruits and vegetables) provide vitamins, minerals, antioxidants, and phytonutrients such as polyphenols that maintain vascular health and decrease inflammation. Importantly, evidence suggests that for cardiovascular health, the antioxidants should be in food form - not isolated supplements.

EATING FEWER HIGHLY PROCESSED FOODS

...particularly those containing saturated, trans, and hydrogenated fats as well as high levels of salt and sugar. The saturated, trans, and hydrogenated fats in many highly processed foods can contribute to cardiovascular diseases by increasing inflammation and vascular stiffness. A high sugar intake is also associated with CVD; thus, eating less sugar can help decrease risk.

EATING ENOUGH FIBER

Fiber helps with a healthy lipid profile in part by binding to excess cholesterol and removing it from the body.

CONSUMING HEALTHY FATS

The fats we eat can change our lipid profile and inflammation. For instance, many fatty acids, such as omega-6s and omega-3s, are involved in synthesizing eicosanoids, hormone-like substances that affect many physiological processes, including in the cardiovascular system, such as:

• The contraction and expansion of blood vessels

• Blood coagulation

• Blood lipid metabolism

Healthy fats from minimally processed foods like nuts, seeds, fatty fish, avocados, and olive oils can thus improve lipid health, keep cell membranes fluid, and decrease inflammation. Omega-3 fatty acids in particular can also help decrease blood clotting.

CONSIDERING INDIVIDUAL SODIUM NEEDS

Blood pressure is regulated by several factors, including minerals such as sodium (i.e., salt). Sensitivity to sodium goes up during menopause, and overconsumption of sodium (e.g., from eating lots of highly processed foods) can lead to more fluid retention and higher blood pressure, which can potentially increase the risk of stroke, heart attack, and other conditions, particularly in older adults.

Ideally, salt intake should stay under 2300 milligrams daily for most women.

For those over-consuming sodium, eating less salt may be one strategy to help reduce blood pressure if that's a health concern for them. This is something they should discuss with a physician or a registered dietitian.

That said, too little intake may be problematic too. In some unique cases, you may benefit from lightly salting your food or using an electrolyte drink if:

• You're very active and sweat a lot (in which case, you'll sweat excess salt and may need more sodium to help prevent dehydration).

• You live in a very hot or dry climate, or at a high altitude.

• You urinate very frequently and have a hard time feeling hydrated even when you're drinking a lot of water throughout the day.

• You get frequent muscle cramps (e.g., during exercise, at night).

There are also some medical considerations that may benefit from salt intake. For example, if you're taking a diuretic, you have diagnosed low blood pressure, or you notice symptoms like feeling faint or dizzy when going from sitting to standing.

Again, I encourage you to consult with your doctor or a registered dietitian about specific salt intake recommendations.

CHOLESTEROL, LIPOPROTEINS, AND CARDIOVASCULAR RISK

There's a common myth out there that all cholesterol is bad and increases cardiovacular risk. But, as is often the case in nutrition, things aren't that simple.

Here's what you need to know.

Cholesterol is a fatty, waxy substance that our body makes and that can be found in food. We use it to form cell membranes and many key molecules, like sex hormones.

Because it's fatty, cholesterol can't travel on its own in our water-based bloodstream. So, it needs to be transported around the body using special proteins called lipoproteins.

There are many types of lipoproteins with different densities and sizes. These properties are what create their relative cardiovascular health risk or safety. For example:

• Low-density lipoproteins (LDL), carry lipids like cholesterol to tissues from the liver. High levels of LDLs may increase CVD risk.

• High-density lipoproteins (HDL), carry cholesterol back to the liver for recycling. They're associated with lower CVD risk.

The Role of LDL In Heart Disease

Why is high LDL asociated with a higher risk of heart disease? The answer lies in the properties of lipoproteins.

LDLs are bigger and fluffier. They're also more prone to get stuck somewhere, like the inside of a blood vessel.

This of this like the crud that builds up in your sink drain. When enough crud (in this case, LDL particles, their constituent proteins, and the cholesterol they contain) builds up on a blood vessel wall, it stimulates an immune system response. This immune response sends white blood cells to the site and stimulates inflammation. Over time, if this inflamed fatty plaque buildup isn't cleared out and the inflammation isn't resolved, it gets bigger and bigger... until the vessel is partially or fully blocked.

Atherosclerosis - the narrowing and hardening of blood vessels due to blockage and inflammation - is the main cause of heart attacks and strokes.

So cholesterol itself isn't to blame - rather, the problem is the "container" it might be traveling in. HDL transporters are considered "healthier" because they help transport cholesterol back to the liver for recycling, and their smaller, denser particles don't seem to contribute to cardiovascular disease.

The Role of Diet in Lipoprotein Levels

As women age, their cardiovascular health profile changes. With menopause, LDLs, triglycerides, and overall cholesterol levels go up. But their diets - especially the type of fats they eat - can significantly affect their llipid and lipoproein profile.

So should you limit the cholesterol you eat?

Short answer: Not necessarily.

Dietary cholesterol itself doesn't seem to affect CVD risk nor cardiovascular health.

The liver tightly regulates how much cholesterol is made and circulating in the body. Excess cholesterol can bind to dietary fiber and be excreted in poop. (This is one reason eating fiber is good for us.)

What does seem to affect this cardiovascular health profile isn't dietary cholesterol per se. Rather, it's what fatty acids we regularly consume.

• Likely helpful: Omega-3s and minimally processed plant fats from nuts, seeds, avocados, olives, and olive oil seem to improve our lipid health by lowering LDL levels and increasing HDL levels.

• Likely not helpful: Saturated fats from animal products - particularly highly processed animal foods (e.g., hot dogs, lunch meats) and trans and highly processed fats (e.g., cooking spray, margarine) - seem to worsen our lipid profile by raising LDL and lowering HDL levels.

Foods like shrimp that are high in cholesterol but low in saturated or trans fats aren't a health risk. And good news for egg lovers: They're probably fine too (not to mention a great source of nutrients like choline, which helps protect our brain). However, you may want to cook them in olive oil instead of butter.

What This Means for You

Diet is important, but just one of the many factors in cardiovascular health.

For instance, people can also vary genetically in their lipoprotein, triglyceride, and cholesterol profile.

A diet that works great for one person may not suit another. This means it's important for you to get regular medical checkups that include a lipid panel (a blood test that shows levels of LDLs, HDLs, triglycerides, and overall cholesterol) to accurately assess cardioivascular health.

WHAT YOU CAN DO

Here are some ways you can boost your cardiovascular health:

• Follow the foundational nutrition skills previously discussed in this course.

• Include regular physical activity.

• Get regular medical checkups, including cardiovascular health assessments. Aside from aerobic fitness, general cardiovascular health can be hard to see from the outside. It's important to check regularly with lab tests that can show blood markers.