Vitamin D May be the Answer For Young Adults To Fight Colorectal Cancer

Health Magazine

Cases of cancer have been climbing each year. These could be brought about by changes in lifestyle and dietary patterns. They say that these are the culprits that may be partly to the reason behind the increasing incidence of colorectal cancer, especially among the younger adults.

Scientists have hypothesized and speculated about this and say that they also noticed a decline in the average dietary intake of vitamin D since the 1980s. Could this be why? They wanted further clarity and conducted a study. The results showed interesting facts. They have found an association between a higher total intake of vitamin D and a lower risk of colorectal cancer in adults, particularly those younger than 50 years old.

The findings were clear and the answer could be encouraging people in this age bracket to increase their vitamin D intake. While medicines are effective, this option provides a cheap, low-risk complement to screening for the disease.


All about Colorectal Cancer

Colorectal cancer (otherwise known as cancer of the colon or rectum) is the third most common cancer in the world. This is also the third leading cause of cancer-related deaths in the United States alone. While the general incidence of colorectal cancer has lowered over the past 20 years, the number of younger adults with the disease has unfortunately gone up.

If the present trend continues, researchers have already come up with an alarming estimate. They said that by 2030, almost 11 percent of colon cancers and 23 percent of rectal cancers will occur in those under 50 years old. Moreover, around 50 percent of the people with early-onset colorectal cancer actually don’t have a family history of the disease or even known genetic risk factors. This could mean that the changing lifestyles and dietary patterns could be the sole perpetrator behind the increasing incidence.

Researchers have also looked into the connection between early-onset colorectal cancer to obesity and sedentary lifestyles. With this, they honed in on the changes in diet as another possible for the slowly rising statistics. The researchers suggest that less consumption of foods rich in vitamin D could be the prime suspect. Hence, it’s important to include dairy products, fish, mushrooms, and eggs when eating. That’s because the related studies have found that vitamin D helps fight colorectal cancer. Unfortunately, these studies haven’t concentrated on the early onset form.

Kimmie Ng, M.D., M.P.H., who directs the Young-Onset Colorectal Cancer Center at the Dana-Farber Cancer Institute in Boston, MA., said, “Dietary changes in recent decades are one of the many potential risk factors that we are studying in relation to young-onset colorectal cancer.”

The doctor spoke to Medical News Today about this and explained, “We know that diet and lifestyle are strongly linked to colorectal cancer overall (no matter what the age of diagnosis), so it makes sense to explore whether some of the risk factors that have changed recently — like vitamin D — may be contributing to the rise of young-onset colorectal cancer.”


Vitamin D Provided by Diet and Supplements

Dr. Ng and her colleagues at the Harvard T.H. Chan School of Public Health in Boston, MA, and other institutions analyzed the data found on people’s diet, lifestyle, and medical history. They collected data from 116,429 female nurses between 25 to 42 years of age. The nurses were participants in the Nurses’ Health Study II (NHS II) that started in 1989. In this prospective study, participants were asked to fill out questionnaires every two years. They had to provide information on their lifestyle, medical, and other health-related information. They also answered questions about their diet in a food frequency questionnaire every four years, which they answered in more detail.

The researchers then gathered the data and estimated the volunteers’ total vitamin D intake found in their diet and supplements. Between the years 1991 and 2015, there were 111 newly diagnosed cases of early-onset colorectal cancer among the participants involved. The researchers also made adjustments for other known risks such as smoking, drinking alcohol, red meat consumption, and sedentary behaviors. They still discovered that total vitamin D intake was essentially and vitally associated with a reduced risk of early onset colorectal cancer.

When it comes to protection from colon cancer, it showed to increase with vitamin D intake. These are available from dietary sources such as dairy products. These are actually better than the ones you get from supplements. The scientists also discovered a link between low vitamin D intake and the appearance of precursors to the disease. These are known as adenomas and polyps.

Dr. Ng said, “Our findings suggest that as little as 300 [international units or IU per day] of vitamin D (approximately 3 glasses of milk per day) may be associated with a 50% decreased risk of young-onset colorectal cancer.” Comparative studies were also made and because of the findings shown, the Institute of Medicine in the U.S. recommends that adults take 600 IU of vitamin D per day. The details of findings are found in the journal Gastroenterology.

The authors came to a conclusion after the elaborate research made. They say that once the link between Vitamin D and colorectal cancer has been confirmed, their findings could bring about recommendations for higher vitamin D intake. This is deemed to be good news because it is an inexpensive, low-risk complement to colorectal cancer screening to prevent the disease for those under the age of 50.


The Link Found in the Reduced Consumption of Dairy

As mentioned previously, the research conducted found a particularly solid connection between vitamin D intake from dairy sources and reduced risk of colorectal cancer.

Lead author Hanseul Kim, a Ph.D. candidate at Harvard T.H. Chan School of Public Health, spoke to MNT and said that decreased dairy consumption since the 1980s might partially tell you more about the increasing incidence of early onset colorectal cancer. She said, “Although the overlap in time trends could be a coincidence, it is interesting that the increased early-onset colorectal cancer incidence and decreased dairy consumption happen around the same time around the world.”

She said that discovering how dietary vitamin D appeared to have a stronger protective effect than the vitamin found from supplements could also be because of chance. She explained, “Another possible explanation might be that certain nutrients in multivitamins could offset the beneficial effects of vitamin D.” Dr. Kim also added, “There could also be additional factors in diet such as calcium that might work with vitamin D to lower risk.”

The author of the study also highlighted the fact that they do not fully understand the mechanism underlying the possible differences between dietary and supplemental vitamin D just yet, but that there seems to be strong data that it does.


More Research Needed to Prove Theory

Manju George, M.V.Sc., Ph.D., medical affairs consultant at the Colorectal Cancer Alliance, shared his thoughts to MNT and said that young-onset colorectal cancer represents more than 10 percent of all colorectal cancer cases. More importantly, the incidence has increased in the last few years.

She said, “Observational studies such as this one shed some light on the role of diet and specific factors like vitamin D toward the increased incidence of young-onset [colorectal cancer], but more research is necessary to draw conclusions.”

The doctor also added and explained, “As the study authors have concluded, further work with a larger sample size to confirm these results needs to be done before adequate vitamin D levels as a strategy for potential [colorectal cancer] risk reduction in young adults can be recommended.”

The authors  also opened up about the several limitations seen in their research. In particular, the relatively small number of cases of early-onset colorectal cancer in the course of the study has placed limitations on its statistical power. They just need more participants to make the case stronger, and while this may be true, they have stressed that the relationship between vitamin D intake and the incidence of precursors of colorectal cancer, which were far more plenty, gave way to the results they found.

Another major limitation of the study has been made. They say that that participants of the study were all women and were mostly from the Caucasian race. Hence, there is a possibility that findings they have may or may not apply to males and non-white racial or ethnic groups. Further analysis should also be required to make the study encompass a wider range of cases from people belonging to all walks of life.