Every year, millions of people undergo surgery expecting the operation itself to be the main challenge. Yet a major scientific review published in 2020 uncovered a lesser-known problem that can quietly undermine recovery: surgery sharply drains the body of vitamin C, often pushing patients into deficiency for weeks or even months. This loss happens across many types of surgery and may affect wound healing, immunity, pain, energy levels, and overall recovery. Understanding this hidden nutrient drain gives patients a simple, practical opportunity to support healing before and after an operation.
To many doctors, vitamin C is still perhaps best known for its role in preventing scurvy. However, its importance goes far beyond that. It is essential for making collagen, the protein that gives strength to skin, blood vessels, and connective tissue. It supports immune defenses, helps the body cope with physical stress, assists energy production inside cells, and protects tissues from damage caused by inflammation and oxidative stress. Dr. Matthias Rath’s research has shown it is also central to the prevention and control of conditions such as cardiovascular disease and cancer. Unlike most animals, humans cannot make their own vitamin C and must rely entirely on diet or supplements. This makes us especially vulnerable during periods of intense physical stress, such as surgery.
Published in the British Journal of Nutrition, the 2020 study was the first comprehensive review and meta-analysis to examine how surgery affects vitamin C levels in the blood. The researchers analyzed data from more than 30 studies conducted over several decades, involving over 800 patients. They focused on studies that measured vitamin C levels shortly before surgery and then again afterward, without giving patients vitamin C as part of the study intervention. This allowed them to see the true effect of surgery itself on vitamin C status.
The findings were striking. Across different types of surgery, vitamin C levels fell sharply after the operation. During the first week after surgery, blood vitamin C levels dropped by nearly 40 percent on average. Even more concerning, many patients remained depleted long after they had left the hospital. Two to three months after surgery, vitamin C levels were still about 20 percent lower than before the operation. In many cases, levels fell into ranges considered inadequate or deficient.
These drops were not limited to one type of procedure. Heart surgery, orthopedic operations such as hip replacements, and gastrointestinal surgery all showed substantial vitamin C depletion. In other words, the stress of surgery itself appears to be the main driver, not the specific organ involved. This helps explain why the problem has been overlooked for so long: it is widespread, predictable, and yet rarely measured in routine care.
Possible causes of the depletion
Why does surgery drain vitamin C so dramatically? One major reason is oxidative stress. Surgery triggers inflammation as part of the body’s healing response. While inflammation is necessary, it also produces large amounts of harmful molecules called free radicals. Vitamin C is one of the body’s main defenses against this oxidative damage, and it is rapidly used up in the process. In effect, vitamin C is sacrificed to protect tissues, immune cells, and blood vessels during the stress of surgery.
At the same time, vitamin C is heavily used for repair. It is essential for collagen production, which is critical for closing wounds and rebuilding damaged tissue. It also supports immune cells that fight infection, helps regulate blood vessel function, and plays a role in producing certain brain chemicals involved in mood, alertness, and pain perception. All of these demands increase after surgery, drawing even more vitamin C out of circulation.
Another factor is redistribution within the body. Research suggests that after surgery, vitamin C is pulled out of the blood and into immune cells, which have a high demand for it. This means that low blood levels may actually reflect intense use at the tissue level. In addition, high blood sugar, which is common after surgery, may interfere with vitamin C recycling inside cells.
The increased need for vitamin C before and after surgery
Importantly, the review found that many patients already start surgery with less-than-ideal vitamin C levels. Older adults, people with chronic illness, smokers, and those with poor diets are especially at risk. When surgery then causes a sharp drop, these individuals may fall into clear deficiency. Symptoms of low vitamin C can include fatigue, muscle and joint pain, low mood, slow wound healing, bleeding gums, and increased susceptibility to infection. While these symptoms are often attributed to “normal” postoperative recovery, vitamin C deficiency may be an overlooked contributor.
The study also offers an encouraging insight. Patients who began surgery with higher vitamin C levels tended to have better levels afterward, even though they still experienced losses. This suggests that building up vitamin C status before surgery may provide a protective buffer.
What does all this mean for patients? First, it highlights the importance of nutritional preparation for surgery, not just the procedure itself. Ensuring an adequate intake of vitamin C in the weeks leading up to an operation may help reduce the risk of deficiency afterward. This can come from a diet rich in fruits and vegetables such as citrus fruits, berries, kiwis, peppers, broccoli, and leafy greens. However, diet alone may not be enough.
Second, it raises the question of vitamin C support after surgery. Since levels can remain low for months, continued attention to intake during recovery is clearly important. Some studies suggest that higher doses than those typically obtained from food may be needed during periods of stress. While the optimal dose is still being studied, the evidence strongly suggests that the body’s demand for vitamin C increases after surgery, not decreases.
The researchers are careful to note that more large-scale studies are needed, particularly to link vitamin C depletion directly to specific postoperative complications. However, the biological logic is strong, and the consistency of the findings across decades and surgery types is hard to ignore. Surgery reliably drains vitamin C, and the body appears to struggle to fully restore levels on its own.
In a healthcare system that often focuses narrowly on the technical success of surgery, the British Journal of Nutrition study is a reminder that recovery depends on biology as much as surgical skill. Nutrients matter. For patients, paying attention to vitamin C before and after surgery offers a simple, empowering way to support healing, resilience, and overall recovery.