To quote Thomas Sydenham, an English physician (1624-1689), “A man is only as old as his arteries.” His belief was certainly ahead of his time since we now know that arterial aging is one of the mechanisms for chronic illnesses such as heart attacks, strokes, dementia, erectile dysfunction and more.
Plaque formation starts to develop early in adulthood as revealed by many autopsies that were performed on men who died in earlier wars. As plaque forms in the arterial wall, the flexibility of the arteries diminishes, the arteries become stiff, the pressure within the arteries increases and this places a strain on the heart which can lead to heart failure if not treated.
As plaque builds up, it decreases normal blood flow; and, if a piece of the plaque comes lose, it flows downstream and eventually comes to rest in the smallest blood vessel. This blocks blood flow to the organ it supplies causing damage to the organ which is known as a heart attack when it involves the heart or a stroke when it involves the brain.
The causes of arterial aging include inflammation, oxidative stress and immune dysfunction. Inflammation occurs as a result of high cholesterol, toxins within the blood, elevated sugar, high blood pressure and more. Inflammation starts the process of plaque buildup and, if not treated, the plaque continues to enlarge resulting in the events described above.
Oxidation (think of how metal rusts when left in the rain) occurs when the body is exposed to stress of any kind whether it comes from mental stress, elevated Cortisol, heavy metal toxins in the blood or poor nutrition with a lack of antioxidants.
Immune dysfunction occurs as a result of the body being exposed to toxins in the food, water, air and the environment. It can also be a result of chronic infections, hormone imbalance or deficiencies of essential vitamins, minerals and other nutrients.
These three mechanisms (inflammation, oxidative stress and immune dysfunction) all affect the ability of the arteries to make nitric oxide which is essential to maintain normal, healthy arteries. Nitric oxide is a vasodilator, which means it dilates/enlarges the arteries so that blood can flow easier.
High blood pressure injures the inner lining of the arteries (the endothelium). When this occurs and the endothelial cells lining the inner part of the arteries are damaged, the production of nitric oxide decreases and the arteries cannot dilate as they should.
Interestingly, research has shown that the bacteria in the mouth help make and recycle nitric oxide and play a role in either maintaining normal blood pressure or in the development of hypertension (high blood pressure).
The SPRINT trial showed that decreasing the systolic blood pressure (the top number in the blood pressure reading) from 140 down to 120 decreases the risk of heart attacks, heart failure and strokes by 1/3 and decreases the risk of death by 1/4.
In addition to lowering blood pressure, nitric oxide also functions to keep all other areas of the body healthy by ensuring normal blood flow through the arteries to all cells in every organ. Without nitric oxide, the red blood cells would not be able to carry oxygen; and, if this did not happen, life would cease.
It is important to realize that endothelial dysfunction is a process. In a newborn, the arteries are completely healthy but soon after birth, the child is exposed to all the things mentioned above which starts to make the arteries unhealthy. As this occurs throughout life, the production of nitric oxide decreases and the cells throughout the body begin to and continue to age.
Researchers have also shown that oral hygiene negatively affects the production of nitric oxide. Bacteria in the mouth chemically alter nitrates to nitrites which are eventually chemically changed into nitric oxide. As such, brushing the tongue and using lots of mouthwash can kill the very bacteria we need to make nitric oxide. In one study, one week of Chlorhexidine mouthwash produced a 26 mmHg rise in blood pressure in those participating in this research!
Please don’t misunderstand. We need to keep the mouth clean from pathogenic/disease producing bacteria. This is essential for not only the health of the teeth and gums but also for the health of the heart. Pathogenic bacteria in the mouth can get into the bloodstream and attach to cells in the heart causing damage. We need to keep the mouth clean, while at the same time, not so clean that we remove the essential bacteria.
Stomach acid is involved in the process where nitrate is converted to nitrite and then to nitric oxide; therefore, getting rid of stomach acid makes it harder for the body to make nitric oxide. Since many people use medications to fight heartburn which decreases stomach acidity, in this situation the individual has a decreased ability to make nitric oxide.
One healthy source of dietary nitrates is vegetables and this is probably the reason we see a blood pressure lowering effect of diets which recommend lots of vegetables. For the reader interested in reading more about this, the reference is in the journal Hypertension 2015 Feb; 65(2):320-327 and the author is Kapil. Specific foods high in dietary nitrates include spinach, broccoli, celery, cabbage and even lettuce. The amount depends on where the veggies are grown. There is significant geographic variability in the amount since the soil in different areas of the country contains different nutrients. Nonetheless, eating more veggies and some fruits daily increases dietary nitrates and, as such, allows the body to make more nitric oxide.
Since high blood pressure injures the endothelial lining of the arteries and decreases nitric oxide levels, we need to pay close attention to individuals with hypertension since this is the #1 risk factor for cardiovascular disease.
In America, 2/3 of the population have either pre-hypertension (SBP 120-139) or have hypertension (SBP 140); and of those, 50% are on medications but are not at their goal blood pressure. This means treatment is not effective to lower the pressure to a level which lowers the risk of heart attacks, heart failure, strokes and kidney problems. In a report from Health Technology Assessment 2003: <7(31): 1-94, it was stated that a decrease of only 5 mmHg in the systolic blood pressure decreased the risk of strokes by 34% and the risk of heart disease by 21%.
Therefore, one way to decrease the age of the arteries is to lower the blood pressure and one way to do this is by eating 5-6 servings of high nitrate vegetables daily. Also, keep the mouth clean but not too clean. Exercise also lowers blood pressure as does stress reduction and sleep. All of the lifestyle behaviors written about so often not only lower blood pressure and the risk of disease but they also improve the quality and longevity of life.
Note from the editor: If you want to treat high blood pressure naturally, you may be wondering which vegetables have the most nitrates. The following video from Food Revolution Summit speaker Michael Greger, MD, discusses the top 10 widely available sources of nitrates.
Here are the top 10 sources of nitrates for lowering blood pressure the natural way:
- Butter leaf lettuce
- Spring greens, like mesclun mix
- Beet greens
- Oak leaf lettuce
- Swiss chard