The Importance of Understanding Endothelial Dysfunction
The Importance of Understanding Endothelial Dysfunction
By Dr. Alan Pressman, DC, CNS, DAC, BN
Endothelial dysfunction is a fancy word for a condition where the inner linings of blood vessels are not functioning correctly. This is because of three issues – reduced vasodilation (the opening of the artery when the heart pumps), inflammation of the lining of the artery, and the formation of clots. The endothelium (a layer of cells that line the blood vessel) is like a retaining wall with tiny leaks; without the leaks, the wall would crack and fall apart. In the case of the artery, tiny gaps between the cells that line the artery allow for important cells, fluids, nutrients, gases and waste to move in and out of the circulatory system.
The artery has three layers - a thick outer layer of connective tissue, a middle muscular layer and a very thin, delicate inner layer known as the endothelium. There are a number of theories about how the innermost part of an artery can become scorned and damaged. One theory is called the “inflammation theory” , which states that very low grade inflammation (almost too small to detect) irritates the endothelium, causing scarring. This results in the formation of plaque and eventually blockages.
Another theory is the “low grade scurvy” theory , which says that people with low vitamin C levels in their diet have susceptibility to artery weakness because of weakened collagen. Collagen is the glue that holds us together. Without strong collagen, arteries get leaky and plaque forms in order to plug the holes. Nonetheless, preventing plaque in the vascular system is essential for avoiding heart attacks, strokes and peripheral vascular disease – the number one problem for diabetics.
Diabetes presents a particular complication to the circulatory system because high sugar in circulation will trigger the liver to want to store that sugar away as fat ; a process some have called the “rainy day effect”. Throughout history, humans have developed different methods of storing energy to protect themselves in times of famine. Biologically, the liver should work in the same way - creating cholesterol and triglycerides from excess sugar and storing it as fat for when it is needed. Except, in our modern society, that rainy day never comes. So, if you’re diabetic, how can you protect your arteries? First, you are going to want to maintain your blood sugar level in the 80-110 mg/dL range. Doctors are obsessed with this number because, once the number creeps up, we start to see blood fats increasing, plaque forming, glycation occurring and more. To protect the arteries, it is critical to be mindful about consuming more protein than carbohydrates, more vegetables than fruits and avoiding refined carbohydrates like the plague.
There are particular foods that support immunity and are high in the vitamin C complex. When choosing which foods support the immune system and keep bacteria in check, remember this clue: “If it stinks, it helps!” Garlic, onions, shallots, scallions, leeks and chives are the foods you will want to eat in this case, as they are all in the allium family of root vegetables, contain sulfur and have anti-bacterial minerals. Garlic has a special compound that does a lot more than repel vampires; it has an active constituent called allin, which is converted by the enzyme allinase to allicin, a phytonutrient that is antibacterial. Though onions contain sulfur, they also contain a special nutrient called quertin and, when this phytonutrient gets metabolized in the gut, it supports healthy vascular function. Dr. Paul Kroon, lead researcher from the Institute of Food Research in the UK, found that metabolized compounds in onions, following digestion, supported the lining of blood vessels. Eating onions produced a low dose of these compounds, but had a large impact.
Dr. Kroon also stated, “We tested compounds that are actually found in the blood, rather than the flavonoid in food before it is eaten, as only these compounds will actually come into contact with human tissues and have an effect on arterial health. The research found that, in the case of one inflammatory process, a lower dose of the compounds (achievable by eating 100g to 200g of onions) actually had a bigger impact.” Shallots, scallions, leeks and chives are no different, so be sure to include these foods in your diet too!
Some whole grains, like buckwheat, are known to support the vasculature with a compound known as rutin, a flavonoid of a different variety. We are talking about the whole grain – little pyramid-shaped kernels – and cooking them just like you would oatmeal (2 parts water, one part buckwheat). Eating to reduce endothelial dysfunction has a very interesting connection to a particular molecule known as nitric oxide. You might have heard of its other name, “laughing gas”, but this is no laughing matter! Nitric oxide is an amazing molecule that actually helps to dilate blood vessels and improve blood flow. In many medical applications, it has proven to be useful therapeutically. But the amazing thing is that our own bodies can produce this molecule when we eat the right foods.
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