Eggs are one of the most popular foods in the world. They are affordable, easy to prepare, and packed with nutrients.
Many people eat eggs regularly for breakfast, lunch, or dinner because they provide high-quality protein, vitamins, minerals, and healthy fats. For years, eggs have been considered an important part of a balanced diet.
However, a new study from Harvard University has raised questions about whether eating larger amounts of eggs could be linked to a higher risk of certain hormone-related cancers.
The findings do not suggest that eggs are dangerous or that people should stop eating them. Instead, the research highlights a possible connection that deserves further investigation.
The study was led by researcher N. Keum and colleagues and was published in the British Journal of Nutrition. The researchers wanted to better understand whether egg consumption might influence the risk of developing cancers that are affected by hormones, including breast cancer, ovarian cancer, and prostate cancer.
To explore this question, the team conducted a dose-response meta-analysis. This type of research combines results from multiple previous studies and examines how different levels of exposure—in this case, egg consumption—may be associated with health outcomes.
By combining data from many studies, researchers can identify patterns that may not be obvious in individual studies alone.
The analysis found that women who ate five or more eggs per week had a higher risk of developing breast cancer compared with women who rarely or never ate eggs. The researchers also found a similar association between higher egg consumption and ovarian cancer risk.
For men, the results were slightly different. Eating five or more eggs per week was not linked to a higher risk of developing prostate cancer overall. However, among men who did develop prostate cancer, higher egg consumption was associated with a greater risk of dying from the disease.
These findings attracted attention because hormone-related cancers are among the most common cancers worldwide.
Breast cancer is the most frequently diagnosed cancer among women, while prostate cancer is one of the most common cancers in men. Understanding how lifestyle factors such as diet might affect these diseases is an important area of research.
The researchers emphasized that their study does not prove that eggs directly cause cancer. This is an important distinction. Observational studies can identify associations between two factors, but they cannot prove that one factor causes the other. Many other influences may contribute to the increased risks that were observed.
For example, people who eat more eggs may also have different eating habits, exercise patterns, smoking histories, or health conditions compared with those who eat fewer eggs. Genetic factors, environmental exposures, and overall lifestyle choices may also play important roles.
Scientists are still exploring possible biological explanations for the findings. Eggs contain cholesterol, choline, and several other nutrients that may influence hormone activity, inflammation, or cell growth.
Some researchers have suggested that these factors could potentially affect the development of hormone-related cancers. However, the evidence remains incomplete, and much more research is needed before firm conclusions can be drawn.
The relationship between eggs and cancer has been studied for many years, but previous research has produced mixed results. Some studies have reported increased risks, while others have found little or no connection. Differences in study design, population groups, dietary habits, and methods of analysis may explain some of these conflicting findings.
One strength of the Harvard-led analysis is that it examined a large amount of data and looked at how risk changed with different levels of egg consumption. This provides a broader picture than many earlier studies.
Even so, experts generally agree that no single food determines a person’s cancer risk. Cancer is a complex disease influenced by many factors, including age, family history, body weight, physical activity, smoking, alcohol consumption, environmental exposures, and overall dietary patterns.
Most nutrition experts continue to recommend focusing on a balanced diet that includes a variety of healthy foods. Fruits, vegetables, whole grains, legumes, nuts, and lean protein sources have all been associated with better long-term health outcomes.
Eating a wide range of foods helps ensure that the body receives the nutrients it needs while avoiding excessive reliance on any one food.
For people who have a family history of breast cancer, ovarian cancer, or prostate cancer, these findings may be worth discussing with a healthcare professional. A doctor or dietitian can help assess individual risk factors and provide personalized dietary advice.
The study does not suggest that people should eliminate eggs from their diet. Instead, it supports the idea of moderation and informed decision-making. Eggs remain a nutritious food for many people, but like many aspects of nutrition, the amount consumed may matter.
As scientists continue to study the connection between diet and cancer, future research may provide clearer answers about how eggs influence health.
Until then, maintaining a balanced diet, staying physically active, avoiding smoking, and attending regular health screenings remain some of the most effective ways to reduce overall cancer risk and support long-term wellbeing.
If you care about cancer, please read studies that a low-carb diet could increase overall cancer risk, and vitamin D supplements could strongly reduce cancer death.
For more information about health, please see recent studies about how drinking milk affects the risks of heart disease and cancer and results showing higher intake of dairy foods linked to higher prostate cancer risk.
