Relaxin is a polypeptide hormone belonging to the insulin superfamily, most famously recognized for its role in preparing the body for childbirth. While its ability to loosen ligaments during pregnancy is widely known, modern research highlights its broader influence on health, particularly in tissue repair and cardiovascular function. Interest in supporting this hormone often relates to its potential for promoting connective tissue health, reducing scarring, and supporting overall endocrine balance. Since direct dietary increase is not possible, this article explores the biological mechanisms of relaxin and indirect ways to support its production through lifestyle adjustments.
Defining the Relaxin Hormone
Relaxin is a small protein hormone composed of two peptide chains linked by disulfide bonds, similar to insulin. Its action is mediated by specialized receptors, primarily Relaxin Family Peptide Receptor 1 (RXFP1), found on cells throughout the body. The hormone’s physiological functions extend far beyond the reproductive system, impacting crucial processes related to tissue health.
Relaxin possesses powerful anti-fibrotic properties, helping to prevent excessive scar tissue formation in organs like the heart, lungs, and kidneys. It also acts as a potent vasodilator, relaxing blood vessel walls to improve circulation and reduce systemic resistance. Furthermore, it supports angiogenesis, the formation of new blood vessels, and exhibits anti-inflammatory effects that aid in tissue remodeling and wound healing.
Biological Sources and Regulation
The production of relaxin varies dramatically between physiological states, which explains why naturally increasing it presents a challenge. In individuals who can become pregnant, the corpus luteum produces a surge of relaxin following ovulation, and the placenta becomes the major source during gestation. This massive, temporary production is responsible for the hormone’s well-known effects on pelvic joint laxity.
In non-pregnant individuals and males, relaxin is produced at a low, stable baseline level by secondary sources. These sources include the prostate gland, the heart, the brain, and specific cells within the uterus and breast tissue. These baseline levels are tightly regulated by local tissue needs, such as minor wound healing or tissue maintenance, making them difficult to intentionally manipulate. The hormone acts locally, meaning its effects are often restricted to the immediate area of production, making circulating levels less reflective of its activity.
Supporting Hormone Production Through Lifestyle
Since relaxin is a peptide hormone, its concentration cannot be raised simply by consuming a precursor molecule, requiring a focus on supporting the entire endocrine system. Managing chronic stress is a foundational step, as high levels of cortisol can disrupt the delicate balance of reproductive hormone pathways linked to relaxin production. Implementing stress-reduction techniques like mindfulness meditation or ensuring consistent, high-quality sleep helps to lower the chronic cortisol load.
Nutritional support focuses on providing the raw materials and cofactors necessary for hormone synthesis and function. This includes consuming adequate amounts of healthy fats, such as omega-3 fatty acids found in fatty fish and flaxseeds, which are necessary for cell membrane health and hormone messaging. Micronutrients like B vitamins and magnesium are cofactors in numerous enzymatic reactions involved in endocrine regulation, indirectly supporting the systems that produce and utilize relaxin.
Moderate, consistent physical activity also plays an indirect role by promoting healthy circulation and tissue turnover, processes relaxin is involved in. Exercise helps to regulate blood sugar and insulin levels, maintaining the endocrine environment in which all hormones operate optimally. Excessive, high-impact exercise should be approached with caution, however, as it can place undue strain on connective tissues if baseline relaxin levels are low.
Medical Applications and Future Research
While natural methods offer supportive action, true “increases” are currently reserved for clinical settings using synthetic compounds. Recombinant human relaxin, often referred to as serelaxin, has been studied extensively in clinical trials for conditions related to tissue scarring. Its potent anti-fibrotic effect makes it a promising therapeutic agent for treating organ fibrosis in chronic diseases.
Research has primarily focused on acute heart failure, where the hormone’s vasodilatory and anti-scarring properties can improve cardiac function. Researchers are also investigating synthetic relaxin and small-molecule agonists of the RXFP1 receptor for conditions like chronic kidney disease and pulmonary fibrosis. Studies have also explored its potential in treating localized joint conditions, such as arthrofibrosis, by directly injecting the hormone to restore joint mobility and improve tissue health.