Red light therapy, also known as photobiomodulation (PBM), uses specific wavelengths of light (typically 630–700 nm red and 780–1100 nm near-infrared) to stimulate biological processes within cells. This non-invasive therapy is absorbed by cellular components.
A growing area of investigation is whether this light-based approach can positively influence cardiovascular function, specifically addressing high blood pressure, or hypertension. This article explores the scientific understanding of red light therapy’s role in blood pressure regulation and the mechanisms that drive these effects.
The Current Scientific Evidence
Research indicates that red light therapy can lower blood pressure, particularly in cases of hypertension. Studies focusing on individuals with essential hypertension found that patients experienced improved blood pressure readings following treatment. This improvement was observed even in some patients who had not responded well to conventional medications.
The reduction is described as a hypotensive effect, meaning it lowers high blood pressure without significantly altering normal readings. In one analysis of trials, treatments resulted in a mean reduction in systolic blood pressure of approximately 15.87 mmHg and diastolic blood pressure of about 8.73 mmHg compared to control groups. These reductions are considered clinically significant in managing hypertension. Consistent, long-term application is required to maintain a lasting reduction in both systolic and diastolic numbers.
How Red Light Therapy Affects Circulation
The positive impact of red light therapy on blood pressure is rooted in its ability to enhance vascular function at a cellular level. Light energy is absorbed by the mitochondria within the cells lining the blood vessels. This absorption stimulates the release of nitric oxide (NO), a crucial signaling molecule.
Nitric oxide is a potent, naturally occurring vasodilator, causing the smooth muscle walls of blood vessels to relax and widen. This process, called vasodilation, directly improves blood flow and reduces the resistance against which the heart must pump. Lowering this peripheral resistance reduces pressure within the arteries, thereby lowering overall blood pressure.
The therapy also supports vasodilation by reducing oxidative stress and inflammation within the blood vessel walls. Chronic inflammation damages the inner lining of the blood vessels, called the endothelium, impairing its ability to produce nitric oxide. By mitigating this cellular stress, red light therapy helps restore healthy endothelial function, making the blood vessels more responsive and flexible. This improved vascular tone contributes to the sustained reduction in blood pressure readings.
Practical Application and Safety Guidelines
Red light therapy devices for home use include large panels or smaller, handheld models. For blood pressure management, targeting areas rich in blood vessels, such as the chest or abdomen, is often recommended. Treatment sessions generally involve exposure to the light for 10 to 20 minutes per session.
Consistency is necessary to maintain long-term vascular benefits, with a frequency of three to five times per week being common. The therapeutic benefit depends on delivering a specific amount of energy to the tissue, affected by the device’s power and distance from the skin. Users should follow the manufacturer’s instructions regarding distance and time to ensure an effective dose is delivered.
While red light therapy is safe and non-invasive, consultation with a healthcare provider is important before beginning treatment, especially for those with pre-existing cardiovascular conditions. This is crucial for individuals taking blood pressure-lowering medications.
Certain medications can increase the skin’s sensitivity to light (photosensitivity), which warrants starting with shorter sessions and a greater distance from the light source. Users should also use protective eyewear to shield the eyes from the bright light.