Researchers in Spain studied what harmful chemicals called N-nitrosamines people eat in their food, especially focusing on children and older adults. They looked at 671 food surveys from 116 children and 182 adults to measure how much of these chemicals people consume. The study found that processed meats like bacon and deli meat are the biggest sources of these chemicals. Young children around 4 years old and some adults were exposed to levels that health experts say might be concerning. The findings suggest that reducing processed meat, especially for young children and elderly people, could be an important way to lower cancer risk.

The Quick Take

  • What they studied: How much of certain cancer-linked chemicals called N-nitrosamines people eat in their daily food, and which foods contain the most of these chemicals
  • Who participated: 116 children (ages 6 months to 4 years) and 182 adults (ages 19 to 95 years) from northern Spain who filled out detailed food surveys
  • Key finding: Processed meats like bacon, sausage, and deli meat are the main source of these harmful chemicals. Children around age 4 and some adults had exposure levels that experts consider potentially risky, especially when compared to safe daily limits
  • What it means for you: Reducing how much processed meat you and your family eat, particularly for young children and older adults, may help lower exposure to these chemicals. However, this is one study and more research is needed before making major dietary changes—talk to your doctor about your family’s specific situation

The Research Details

Scientists collected detailed food surveys from 298 people living in northern Spain. They asked people to report everything they ate over a period of time using a validated questionnaire—a special survey that experts have confirmed is accurate. The researchers then used existing scientific databases to calculate how much of the harmful chemicals (nitrates, nitrites, and N-nitrosamines) were in each food item. They looked at 348 different foods and measured the chemical content per 100 grams. They then calculated each person’s total exposure based on their body weight, which is important because a chemical that’s safe for an adult might be risky for a small child.

The study was designed to look at different age groups separately because children and elderly people may be more vulnerable to these chemicals. The researchers used a special computer tool to identify which specific foods were the biggest contributors to each person’s exposure. This approach allowed them to see patterns across different ages and identify which groups might be at highest risk.

Understanding which foods contain these harmful chemicals and which age groups are most exposed is crucial for public health. Children’s bodies are still developing, and elderly people may have weaker defenses against harmful chemicals, making them potentially more vulnerable. By identifying processed meat as the main source, this research can help guide recommendations about which foods to limit. The study’s focus on age-specific exposure is important because a safe amount for an adult might be unsafe for a young child.

This study used validated food surveys, meaning the questionnaire has been tested and proven to accurately measure what people eat. The researchers used established scientific databases from major health organizations (EFSA and EPIC) to determine chemical content, which adds credibility. However, the study only included people from one region of Spain, so results may not apply equally to all populations. The study is observational, meaning it shows what people ate but cannot prove that these chemicals directly caused health problems. The sample size of 298 people is moderate—larger studies would provide stronger evidence.

What the Results Show

The study found that processed meats were by far the largest source of N-nitrosamines in people’s diets. The highest exposure occurred in children around 48 months (4 years) old. A specific chemical called NDMA (N-Nitrosodimethylamine) was the most common harmful chemical found.

When researchers looked at safety limits set by health experts, they found concerning results: between 12% and 19% of adults exceeded the acceptable daily intake (ADI)—the amount that health organizations say is safe to consume daily. For children, the situation appeared more concerning. The researchers used a measurement called “margin of exposure” (MOE) to assess risk. When this number is below 10,000, it suggests potential health concern. Children from 12 months through adulthood showed MOE values below this threshold, with the lowest (most concerning) values at 48 months.

In adults, nitrite exposure (one component of these harmful chemicals) came mainly from animal-based foods. The study suggests that early childhood, particularly around ages 1-4 years, may be a critical window when reducing exposure to these chemicals could have the biggest health impact.

The research identified that different age groups had different patterns of exposure. While processed meats were the main source across all ages, the proportion of exposure from different food types varied. The study also found that nitrate and nitrite content varied significantly between different food items, even within the same food category, suggesting that some brands or preparation methods may be safer than others.

This study builds on previous research showing that processed meats contain these harmful chemicals. However, this research is notable for its detailed age-specific analysis, particularly its focus on young children. Previous studies have documented that these chemicals exist in food, but this study provides clearer evidence about which age groups face the highest exposure relative to safety limits. The findings align with existing health recommendations to limit processed meat consumption, particularly for vulnerable populations.

The study only included people from one region of Spain, so the results may not apply to people in other countries with different food sources or eating habits. The study measured what people reported eating, which can be inaccurate—people may forget foods or misremember portion sizes. The study is observational, meaning it shows associations but cannot prove that these chemicals directly caused disease in these individuals. The sample size, while reasonable, is not huge, so results should be confirmed in larger studies. The study doesn’t account for all possible sources of exposure to these chemicals (like drinking water or other environmental sources).

The Bottom Line

Based on this research, health experts may want to consider recommending that families, especially those with young children (ages 1-4), reduce consumption of processed meats like bacon, sausage, deli meats, and cured meats. For older adults, reducing processed meat intake may also be beneficial. However, this is one study, and the evidence is not yet strong enough to make absolute recommendations. Confidence level: Moderate. The findings support existing general health recommendations to limit processed meat, but more research is needed before making major dietary changes. Consult with your healthcare provider about what’s appropriate for your family.

Parents of young children (especially ages 1-4 years) should pay attention to this research, as it suggests this age group may face higher relative exposure to these chemicals. Older adults (65+) should also consider these findings. People with a family history of cancer may want to discuss this with their doctor. People who eat large amounts of processed meat should consider this information. This research is less immediately relevant to people who rarely eat processed meats or who follow plant-based diets, though they may still benefit from the general information.

If families reduce processed meat intake, they would immediately lower their exposure to these chemicals. However, the health benefits (like reduced cancer risk) would take years to become apparent, as cancer typically develops over many years. You might notice other health changes (like improved digestion or energy levels) within weeks to months, but the cancer-prevention benefits would be long-term.

Want to Apply This Research?

  • Track weekly servings of processed meats (bacon, sausage, deli meats, cured meats, hot dogs) consumed by each family member, with special attention to children ages 1-4. Set a goal to reduce servings by 25-50% over 4 weeks and monitor progress.
  • Replace one processed meat meal per week with a plant-based protein source (beans, lentils, tofu) or fresh, unprocessed meat. For example, swap a deli sandwich for a turkey and avocado sandwich made with fresh turkey breast, or replace bacon with scrambled eggs.
  • Use the app to log processed meat intake weekly and track trends over months. Set reminders when shopping to choose fresh meats instead of processed options. Create a family challenge to find and try new recipes that reduce processed meat use while maintaining meals family members enjoy.

This research suggests a potential health concern related to processed meat consumption, but it is observational and does not prove that these chemicals caused disease in the study participants. This information should not replace advice from your healthcare provider. Before making significant dietary changes, especially for children or if you have existing health conditions, consult with your doctor or a registered dietitian. This study was conducted in Spain and may not apply equally to all populations. Individual risk varies based on many factors including genetics, overall diet, and lifestyle. Always seek professional medical advice for personalized health recommendations.