Nitric oxide (NO) is a powerful biochemical gas produced by the body that acts as a cellular signalling molecule. It has an incredibly short half-life of a few seconds and it fulfils a variety of really important roles including the vasodilation and tone of blood vessels, neurotransmission, glucose metabolism, peristalsis, airway tone and angiogenesis. If you have a chronic illness, you’re very likely to be deficient in this incredibly important molecule. In this article I’ll explain how nitric oxide is produced and how to boost your nitric oxide levels naturally. Nitric oxide shouldn’t be confused with nitrous oxide, the anaesthetic commonly used in dentistry.
The synthesis of NO is catalysed by two routes, the main one being production by a family of enzymes called NOS that comprise of three forms: eNOS or endothelial NOS (NOS3), which produces NO in blood vessels and is responsible for vasodilation, nNOS or neuronal NOS (NOS1), is expressed in skeletal muscle and it produces NO in nervous tissue, and iNOS or inducible NOS (NOS2), which is involved in the immune response. This route utilises the amino acid L-arginine, oxygen and the active form of vitamin B3, NADPH.
This pathway is subject to decreased function due to some genetic variants that are very common in the population, as well as ageing.
The other pathway is the nitrate-nitrite-NO pathway
This pathway begins in the mouth and is intrinsically linked with the oral microbiota.
When we ingest nitrate-rich foods such as dark green leafy vegetables or beetroots, the nitrate from the food enters the bloodstream and the salivary glands concentrate it in the mouth, where facultative, anaerobic commensal bacteria living on your tongue reduce nitrate to nitrite via specific reductase enzymes.
These salivary nitrates are then swallowed into the stomach,. Where in contact with hydrochloric acid they are converted to NO. Stomach NO then helps to increase gastric mucus and circulation and is then absorbed into the bloodstream.
Having good levels of stomach acid as well as a balanced oral microbiota are essential for the activation of this pathway. The nitrate-nitrite NO pathway is the main producer of NO over the age of 40. Looking after one’s digestion and microbiota as well as healthy levels of green leafy veggies in the diet is an insurance protection against low levels of NO and the degenerative conditions like Alzheimer’s and cardiovascular disease it is associated with.
SINGS AND SYMPTOMS OF LOW NITRIC OXIDE
- High blood pressure
- Sleep apnoea
- Diabetic ulcers
- Insulin resistance
- Dental caries
- Oral infections
- Low hydrochloric acid
- Age over 40
- Erectile dysfunction
- Benign prostatic hyperplasia
- Altitude sickness
- Alzheimer’s disease
COMMON CAUSES OF LOW NITRIC OXIDE
Oxidative stress: NO is a powerful antioxidant. Being in a state of chronic inflammation will drive deman for NO higher, leading to its depletion as fast as its created.
Poor oral flora: As explained above, oral flora is an essential step in the conversion of dietary nitrates to nitrites. This process is called NO recycling.
Use of antacids and proton pump inhibitors: These decrease or block stomach acid, effectively blocking the NO recycling pathway. Perha[s this ois one of the reasons why people on long term antacids develop so many chronic conditions.
Use of antiseptic mouthwashes: These wipe out the commensal anaerobic flora that converts nitrates to nitrites.
Use of broad spectrum antibiotics: same problem as for the mouthwashes.
Poor levels of hydrochloric acid: Hydrochloric acid helps convert salivary nitrites into
Habitual spitting of saliva: This block the circulation of salivary nitrites into the stomach.
Stress: this is my addition and not one I’ve found support for in the literature. But stress activates the sympathetic nervous system, which decreases production of saliva necessary for nitric oxide recycling.
HOW TO TEST YOUR LEVELS OF NITRIC OXIDE
As NO is a gas with a very short half-life, specialised blood tests are required in order to gauge serum levels. This type of testing isn’t currently available in Australia. In the US — do a blood test that also includes NO levels.
If you’re based in Australia – or in the US – a fariyl accurate way to gauge your NO levels is to use NO testing strips. These are widely available through online supplement companies like iHerb or you can obtain them from your complementary practitioner. We stock these in clinic.
The strips are very simple to use, and non-invasive. The best time to test for NO is first thing in the morning, before drinking or brushing your teeth. If this isn’t possible, you can test any time of day at least 30 minutes after eating. Eating nitrate-rich foods sych as dark green leafies and beetroots may give you a false spike of NO.