The Plant Rx

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Archive for the ‘Depression’ Category

How does a plant-based diet prevent disease? A short lesson

Posted by Jenn on January 31, 2011


There is an ever-growing mountain of evidence substantiating the numerous health benefits that a plant-based diet provides.

This colorized scanning electron micrograph (SEM) of red blood cells in an artery shows a layer of endothelial cells (beige) surrounded by muscle (pink). by: Steve Gschmeissner / Photo Researchers Inc.

Peer-reviewed medical paper after peer-reviewed medical paper published in the most well-respected of journals have shown that a plant-based diet free of meat and dairy products is the single most powerful tool we have at our disposal to prevent and fight disease.

Not only can heart disease and diabetes be prevented but the disease progression can be stopped and reversed. If that wasn’t enough there is a multitude of research showing how the consumption of a plant-based diet’s can prevent cancer, dramatically reduce cancer recurrence rates, reduce cognitive impairment as we age (Alzheimer’s Disease and Dementia) and reduce osteoporosis in addition to a myriad of others. This being the case, how exactly does something as seemingly simple and low-tech as one’s diet manage to do these things?

The short answer is this: via a gas called nitric oxide which is produced by our endothelial cells.  The problem with this very brief explanation is that most people have never heard of nitric oxide, much less endothelial cells. Consequently, that probably isn’t going to help most people understand how the very important the daily decision to eat a plant-based diet is able to accomplish such incredible feats.

What the heck are endothelial cells? and what the heck is Nitric Oxide (NO)? and how do they accomplish the mammoth task of keeping us healthy?

Endothelial cells are the thin single-layer of cells that line the interior surface of all blood vessels.  They are the cells that come in direct contact with blood flowing through our cardiovascular system.  A “healthy” endothelium can be best described as having like a Teflon coating on the vessels’ inner walls; this non-sticky quality enhancing the flow of blood.  An “unhealthy” endothelium, by contrast, acts like Velcro, grabbing white blood cells, platelets and cholesterol and packing them against the inner wall of the blood vessels narrowing them = causing the vessels to thicken over time, thereby inhibiting the flow of blood. This accumulation of “material” leads to the formation of  what are called atherosclerotic “plaques”.

healthy vs unhealthy endothelium

A healthy endothelium is not being covered by any plaque and therefore has the ability to release many beneficial substances into the blood stream.  An unhealthy endothelium  eventually narrows and thickens and resultantly loses flexibility.  The vessels can no longer expand as they should when the heart pumps blood through them. Pumping blood into stiff arteries containing plaque increases resistance to blood flow causing the heart to work harder. Your blood pressure must increase to pump the same volume of blood through these vessels.

That being said, what then determines the overall health of our endothelial cells that make up our endothelium? In other words what makes our endothelium non-stick or sticky?

That is where Nitric Oxide (NO) comes in. Remember, a healthy endothelium is able to release many beneficial substances into our blood stream.  (Note: we are born with a very healthy endothelium which means until we create an environment in which plaques are created, our vessels are healthy, slick and without plaque)  Nitric oxide is one of these substances.  Nitric oxide has a number of important functions.  One of its primary functions according to Dr. Louis J. Ignarro, the 1998 Nobel Prize winner in Medicine,

“…is to help keep the arteries and veins free of the plaque that causes stroke and to maintain normal blood pressure by relaxing arteries, thereby regulating the rate of blood flow and preventing coronaries (heart attacks)”.

He goes on to explain that,

“Nitric oxide is the body’s natural cardiovascular wonder drug”.

NO accomplishes this by controlling muscle tone of the blood vessels which directly impacts blood pressure control, inhibiting the aggregation of platelets and other particulate such as cholesterol and white blood cells.

Other functions worthy of note include: facilitation of proper kidney function, aiding in the transmission of messages between nerve cells, helping the immune system fight  viral, bacterial and parasitic infections as well as tumors, peristalsis, regulating inflammation, lowering of cholesterol levels and penile erection. Let’s discuss one of these functions in more detail to illustrate.

For example, erection of the penis during sexual excitation is mediated by NO release from the endothelial cells lining the blood vessels of the penis.  The NO release from the endothelial cells cause the blood to pool in the adjacent blood sinuses producing an erection.  Thus, if NO cannot be produced (or produced in sufficient amounts) as the result of a damaged endothelium, then an erection cannot occur. This is why difficulty getting or maintaining an erection is indicative of impending or active heart disease (= ample accumulation of plaque).  If you are currently experiencing impotence, it would be a very good idea to see your doctor such that he or she can discern the cause.

How a poor diet results in poor erections

Causes of endothelial damage  and resultant plaque formation:

  • Smoking – it decreases good cholesterol (HDL) and increases bad cholesterol (LDL) that damages your endothelial cells. Further, nicotine directly damages endothelial cells and the carbon monoxide from cigarette smoke damages the endothelium too.
  • A high fat, high cholesterol diet (particularly animal fat from meat and dairy products; plants do NOT have cholesterol) – LDL directly damages endothelial cells.
  • A diet low in fiber content (animal products do NOT contain any fiber) – High fiber foods absorb bile salts that your body uses in digestion.  Your liver manufactures bile from cholesterol.  Thus, high fiber foods are a natural way to reduce bad (LDL) cholesterol.
  • Diabetes – When blood sugars are beyond the normal range it causes oxidative stress to the endothelial cells resulting in damage to them.
  • Being overweight or obese – Fat cells store vitamin D and vitamin D inhibits vessel calcification (plaques eventually get harder as a result of calcification). Thus, losing weight or being at a healthy weight keeps the vitamin D in your system allowing for utilization thereby preventing plaque calcification. Read the rest of this entry »

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Plant-based diet may help depression, dementia

Posted by Jenn on December 20, 2010


(Source: Foodconsumer.org; By David Liu and editing by Rachel Stockton; 07/07/2010)

A new study in the July 6, 2010, issue of Neurology suggests that having depression boosts the  risk of developing dementia, such as Alzheimer’s disease.

The study merely showed an association; the results do not determine whether or not depression causes demention, or vice versa.

The study involved 949 people at an average age of 79 years, who were free of dementia; however, 125 of them were diagnosed with depression at the beginning of the study.

At the end of the 17-year follow-up, 164 participants developed dementia; of those participants, 136 were diagnosed with Alzheimer’s disease.

Jane Saczynski, PhD, author of the study from the University of Massachusetts Medical School in Worcester, MA and colleagues found that 22 percent of those who had depression at baseline ended up developing dementia at the end of the study, compared to 17 percent of those who were not depressed.

Dr. Saczyynski said that even though depression may not necessarily cause dementia, it is possible that something like inflammation of brain tissue contributes to depression and an increased risk of dementia.

Indeed, that is a possibility.  Diet is most assuredly one thing that may affect risk of both depression and dementia.

A study led by Nanri A and colleagues from the National Center for Global Health and Medicine in Tokyo, Japan shows that a plant-based diet protects against depression.

Nanri found a healthy Japanese diet, consisting of high amounts of vegetables, fruit, mushrooms and soy products was associated with fewer depressive symptoms.

Nanri’s findings were reported online in the May 19,2010 edition of the European Journal of Clinical Nutrition.

Another study led by Hughes T.F.(and colleagues) from the University of Pittsburgh School of Medicine suggests that those who consume moderate or high amounts of fruit and vegetables in midlife may help cut their risk of dementia, such as Alzheimer’s disease, in later life.

The association was particularly significant among women,especially those with angina pectoris in midlife, according to the study published in the May 2010 issue of the American Journal of Geriatry and Psychiatry. Read the rest of this entry »

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