Researchers studied how much vitamin D 1,372 Italian adults were getting from their diet. They found that almost everyone—whether healthy or dealing with health problems—was eating far too little vitamin D-rich foods. Men got slightly more than women, and people with less education or plant-based diets had the lowest amounts. The study shows that many Italians are at risk for vitamin D deficiency, which can affect bone health and overall wellness. This suggests Italy needs better strategies to help people eat more vitamin D or consider supplements.

The Quick Take

  • What they studied: How much vitamin D Italian adults were eating from food sources and whether certain groups were getting less than others
  • Who participated: 1,372 Italian adults between ages 40-80 (about 73% women, 27% men). About one-third were healthy, and two-thirds had various health conditions like osteoporosis, kidney disease, or cancer
  • Key finding: People were eating only about 200-250 International Units (IU) of vitamin D daily from food, which is far below the recommended 600-800 IU. Vegans got the least (about 84 IU), and people with less education or living in Northern Italy got significantly less
  • What it means for you: If you’re Italian or follow a similar diet, you likely aren’t getting enough vitamin D from food alone. This is especially true if you’re vegetarian, vegan, have limited education about nutrition, or live in areas with less sun. You may want to talk to your doctor about vitamin D supplements or eating more vitamin D-rich foods like fatty fish, egg yolks, and fortified milk

The Research Details

This was a cross-sectional study, which means researchers took a snapshot of vitamin D eating habits at one point in time rather than following people over months or years. They asked 1,372 Italian adults to report what they ate over 14 days using a detailed food questionnaire. The study included people from different regions of Italy, different age groups, different education levels, and people with various health conditions. Researchers then used statistical tools to compare vitamin D intake between groups and figure out which factors (like age, sex, education, or diet type) were most strongly connected to low vitamin D intake.

Understanding who isn’t getting enough vitamin D from food is important because it helps doctors and public health officials know which groups need help the most. By identifying that vegans, people with less education, and those in Northern Italy get the least vitamin D, health programs can target these groups with better information or food fortification strategies. This approach is more practical than just telling everyone to eat more vitamin D.

This study is reliable because it used a validated food questionnaire (meaning it’s been tested and proven accurate), included a large number of people from different regions, and used proper statistical methods. However, because it’s a snapshot study rather than following people over time, we can see patterns but can’t prove that one thing directly causes another. The study also relied on people remembering what they ate, which can sometimes be inaccurate.

What the Results Show

The most striking finding was how little vitamin D everyone was eating. On average, women consumed only 198.5 IU per day and men 246.7 IU per day—less than one-third of the recommended amount. Even healthy people without chronic diseases weren’t getting enough. The problem got worse with age: older adults ate even less vitamin D than younger ones. People with serious health conditions like osteoporosis, kidney disease, cancer, or neurological problems had the lowest intakes of all.

Certain groups were hit especially hard. Vegans averaged just 83.6 IU daily (about 10% of recommendations), while vegetarians got 152.1 IU. People living in Northern Italy consumed about 53 IU less per day than those in other regions. Those with lower education levels ate about 39 IU less daily than better-educated people. Men were somewhat protected against very low intake compared to women.

When researchers looked at what factors independently predicted low vitamin D intake (meaning they controlled for other variables), they found that being male, having higher education, and living outside Northern Italy were protective factors. In contrast, being vegetarian or vegan, having lower education, living in Northern Italy, and being female increased the risk of getting less than 200 IU daily.

Interestingly, when researchers adjusted their analysis to account for multiple factors at once, age and having a chronic disease were no longer significant independent predictors of vitamin D intake. This suggests that other factors (like education level or diet type) were more important than age or disease status alone. The study also showed that socioeconomic status and education level were strongly connected to vitamin D intake, suggesting that knowledge about nutrition and access to vitamin D-rich foods play important roles.

This study confirms what other research has shown: vitamin D deficiency is a major problem in many developed countries, not just Italy. The extremely low intake levels found here are consistent with previous studies in Europe showing that most people don’t get enough vitamin D from food. The finding that plant-based diets are associated with very low vitamin D intake aligns with other research, since most natural vitamin D sources are animal-based (fish, egg yolks, dairy). This study adds important information by showing how widespread the problem is in Italy specifically and identifying which groups are most at risk.

This study has several important limitations to keep in mind. First, it’s a snapshot in time, so we can’t say whether vitamin D intake is getting better or worse over time. Second, people reported what they ate from memory, which can be inaccurate—some people might remember eating more or less than they actually did. Third, the study only looked at dietary vitamin D intake and didn’t measure actual vitamin D levels in people’s blood, so we don’t know if people were actually deficient. Fourth, the study was done in Italy, so results might not apply to other countries with different climates, food availability, or dietary patterns. Finally, the study couldn’t prove that low education or living in Northern Italy directly causes low vitamin D intake—only that these factors are associated with it.

The Bottom Line

Based on this research, here are evidence-based recommendations: (1) If you live in Italy or follow a similar Mediterranean diet, consider talking to your doctor about vitamin D supplementation, especially if you’re vegetarian, vegan, older, or have a chronic health condition. This is a moderate-confidence recommendation because the study shows very low intake but didn’t measure actual blood levels. (2) Try to eat more vitamin D-rich foods like fatty fish (salmon, mackerel), egg yolks, and fortified dairy products if you eat animal products. (3) If you’re vegetarian or vegan, vitamin D supplementation is strongly recommended since natural plant sources are very limited. (4) Public health officials should consider food fortification programs and public education campaigns about vitamin D, particularly targeting people with lower education levels.

This research is especially important for: older adults (40+), people with chronic diseases like osteoporosis or kidney disease, vegetarians and vegans, people living in Northern Italy or similar climates with limited sun exposure, and people with lower education levels about nutrition. It’s also relevant for doctors, nutritionists, and public health officials planning health programs. People living in sunny climates with good sun exposure and eating plenty of fish and dairy may be less affected, though they should still ensure adequate intake.

If you start taking vitamin D supplements or eating more vitamin D-rich foods, you won’t feel immediate changes. Vitamin D works slowly in your body. It typically takes 4-8 weeks to see improvements in blood vitamin D levels, and 2-3 months to notice potential benefits like improved bone health or energy levels. For people with serious deficiency, it may take 3-6 months of consistent supplementation to reach healthy levels. The key is consistency over time rather than quick results.

Want to Apply This Research?

  • Track daily vitamin D intake in IU (International Units) from food and supplements. Set a goal of at least 600-800 IU daily and log foods like salmon, mackerel, egg yolks, fortified milk, and any supplements taken. Use the app to see weekly and monthly averages to identify patterns.
  • Start by adding one vitamin D-rich food to your diet daily. For example: eat one egg yolk at breakfast, have a serving of fatty fish twice weekly, or switch to fortified milk. If you’re vegetarian or vegan, discuss vitamin D supplements with your doctor and set a reminder to take them daily. Use the app to log these changes and track consistency.
  • Monitor vitamin D intake weekly through the app’s food logging feature. Every 3 months, discuss your intake patterns with your doctor and consider getting blood work done to check actual vitamin D levels (25-hydroxyvitamin D test). Adjust supplementation or dietary intake based on results. Track any changes in energy, bone health, or overall wellness alongside your vitamin D intake to identify personal patterns.

This research describes vitamin D intake patterns in Italian adults and should not be considered medical advice. Vitamin D needs vary by individual based on age, health status, sun exposure, and other factors. Before starting any supplementation or making significant dietary changes, consult with your healthcare provider or registered dietitian. This is especially important if you have kidney disease, heart disease, or take medications that might interact with vitamin D supplements. Blood tests to measure actual vitamin D levels should be ordered by a healthcare professional to determine your individual needs. This study shows associations between factors and vitamin D intake but does not prove that low intake directly causes health problems.