Nutritional status, dietary antioxidant capacity, and dietary diversity in patients with newly diagnosed hematological malignancies: a case–control study

Purpose Nutritional status and dietary antioxidant capacity are important determinants of clinical resilience in cancer; however, data in hematological malignancies remain limited. We aimed to compare nutritional status, dietary total antioxidant capacity (DTAC), and dietary diversity between patients with newly diagnosed hematological malignancies and healthy controls. Methods This case–control study included 34 patients with newly diagnosed hematological malignancies (12 lymphoma, 11 leukaemia, 11 multiple myeloma) and 34 age- and sex-matched healthy controls aged 18–65 years. DTAC was estimated using the ferric reducing antioxidant power (FRAP) method based on a validated food frequency questionnaire. Nutrient intakes and the dietary diversity score (DDS) were derived from 3-day dietary records. Nutritional status was assessed using the Global Leadership Initiative on Malnutrition (GLIM) criteria, along with fat-free mass index (FFMI), and mid-upper arm circumference (MUAC). Results Patients had significantly lower DTAC levels than controls (3.85 ± 1.58 vs. 8.68 ± 3.21 mmol/day, p < 0.05). According to GLIM criteria, 35.3% of patients had moderate malnutrition and 26.5% had severe malnutrition, A declining trend in DTAC was observed with worsening malnutrition ( p = 0.034), although this did not reach the significance threshold after multiplicity adjustment. Low muscle mass was more prevalent in patients as assessed by both FFMI and MUAC. Energy, protein, zinc, vitamin E, and folate intakes were significantly lower in patients (all p < 0.05), whereas DDS did not differ ( p > 0.05). DTAC was positively correlated with intakes of coffee, whole-grain bread, green vegetables, citrus fruits, and fresh fruit ( p ≤ 0.05). Conclusions Significant differences in nutritional status and DTAC between patients and healthy individuals suggest that suboptimal dietary patterns may accompany hematological malignancies at diagnosis. These findings highlight the potential importance of adequate macro- and micronutrient intake; however, further prospective studies are needed to determine whether targeted nutritional interventions can improve clinical outcomes or contribute to long-term risk reduction.