Human cardiovascular system

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Cardiovascular System

If you are dehydrated, your blood volume decreases, so vessel walls do not stretch as much as they should. Baroreceptors relay this information to the brain, which boosts your heart rate to compensate for the reduced blood volume. It may seem counterintuitive, but dehydration can lead to increased blood pressure. Dehydration reduces blood volume, so your body compensates by retaining more sodium in the blood. High blood-sodium concentrations are related to high blood pressure and cause your body to close small blood vessels, the capillaries.

As more capillaries close, the pressure in major blood vessels rises and overall blood pressure further increases. Because the blood has become more concentrated and thicker, it is more difficult to effectively circulate. Your body compensates by "squeezing" blood vessels to help move the blood along, which raises blood pressure.

Cardiac output is the volume of blood that the heart pumps out per beat, multiplied by heart rate. For example, if your heart pumps milliliters of blood per beat and your heart rate is 70 beats a minute, your normal cardiac output would be 7, milliliters a minute. Cardiac output represents how well the heart is delivering blood to the rest of the body.

When you are dehydrated, your cardiac output decreases significantly. Even though heart rate is increased, the amount of blood that the heart can pump per beat is reduced because of overall low blood volume. For example, during dehydration your heart rate might be 90 beats a minute, but your heart might be pumping only 40 milliliters per beat.

The total cardiac output, 3, milliliters per minute, indicates that your heart is much less efficient at providing blood to the rest of your body. Unfortunately, most Americans are missing out on these benefits. Roughly 90 percent of Americans fail to eat the minimum recommended servings of fruits and vegetables, reports the Centers for Disease Control and Prevention. For maximum benefit aim to have five to nine servings of fruits and vegetables each day.

Cutting back on packaged foods is the easiest way to add more fruits and vegetables to your diet. Buy pre-cut fruits and vegetables if you're looking to save time and use them to make healthy snacks and build nutritious plates.

Nut butter on sliced apples, broccoli and carrots with low-fat dressing, and yogurt with fresh berries are examples of easy snacks you can make in a flash. Fish is one of the best sources of heart-healthy omega-3 fats. Wild and wild-caught fish have higher omega-3 levels than farm raised varieties, so skipped farmed fish when possible.

A diet high in omega-3 fats reduces the risk of heart disease. Having at least two servings of fish per week is enough to take advantage of the heart health benefits. Incorporate fatty fish like salmon, herring, mackerel, sardines, rainbow trout and halibut into your diet. Nuts are packed with heart healthy unsaturated fats and eating them helps your heart. Many nuts are high in the same omega-3 fats found in fatty fish.

They're also high in protein and provide a good source of fiber. However, it's important to keep an eye out on your portion sizes. Nuts are dense in calories so about handful is an appropriate serving.

To add more of these heart healthy bits of goodness to your diet, incorporate nuts as a heart healthy snack. Homemade granola with mixed nuts or a serving of nuts with yogurt and berries are just two delicious snack ideas. One of the reasons the Mediterranean diet is considered heart-healthy is its emphasis on unsaturated oils like those found in olive oil. Replacing unhealthy oils with nutritious unsaturated oils is one of the best ways to protect your heart health.

Olive, sesame, avocado and peanut are examples of oils loaded with heart-healthy fats.

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