COVID-19-Related Quarantine Effect on Dietary Habits in a Northern Italian Rural Population: Data from the Brisighella Heart Study

North of Italy was severely hit by the COVID-19 (Coronavirus disease 19) pandemic. This induced the government to adopt severely restrictive measures to reduce the contagion risk, forcing most of the population to stop working and from leisure activities, and to remain at home for several weeks. Our study aimed to evaluate the effect of COVID-related quarantine on smoking and dietary habits of a well-characterized northern Italian rural population. For this purpose, while lockdown restrictions were in place (February–April 2020), 359 subjects from the Brisighella Heart Study cohort underwent a phone interview about their lifestyle habit changes during COVID-19-related quarantine. Quarantine did not significantly modify smoking habit nor body mass index. Subjects significantly increased daily carbohydrates consumption, all fresh vegetables, healthy vegetable oils, milk and yogurt, alcoholic drinks, sugars and sweets, and coffee. The weekly consumption of low-fat meat, cured meat other than ham, cheeses, eggs, nuts and mixed seed oils significantly increased, while the weekly intake of fish, mussels, and legumes significantly decreased during lockdown. The Dietary Quality Index was reduced from 42.4 ± 4.1 to 37.8 ± 4.7 (p < 0.03). In accordance with our findings, COVID-19-related quarantine might worsen the quality of diet, also leading to an increased intake of almost all food categories.