Previous research has addressed the connection between loneliness and malnutrition, and has found that loneliness may affect appetite and nutrient intake through a decline in mood, physical functioning, or cognition [71]. These, in turn, combined with the difficulty of eating alone and changes in social status, particularly due to the loss of a spouse or friends of the same age group, can further inhibit appetite [72]. In comparison, eating with others can help prevent malnutrition. It increases caloric intake, is related to healthier food habits [73,74], and maintains the motivation of older adults to eat and cook, providing them with opportunities for social interaction and connectedness [75]. Another possible explanation is the association between deconditioning and loneliness, deconditioning contributes to frailty and fear of falling. The fear of falling could also contribute to avoiding grocery shopping and a diminished desire to stand while preparing meals. To the best of our knowledge, the finding of a correlation between malnutrition and subjective age is new. It can be explained by the findings of previous research that in older adults, a young subjective age is associated with good health, functional health, and wellbeing [4,45]. Moreover, a comparison between unobserved (blood pressure and telomere length) and observed (grip strength, expiratory flow, and waist circumference) health measures found that the observed health measures were connected to younger subjective age [2]. Against this background, it can be assumed that inadequate nutrition that leads to malnutrition could become an observed health problem that influences functional health. These findings help explain the connection between malnutrition and subjective age.