The long term management of chronic diseases requires adoption of complex dietary recommendations best facilitated via regular coaching to support sustained behaviour change. Telehealth interventions can overcome patient-centred barriers to accessing face-to-face programs and provide feasible delivery methods, as they can be ubiquitous and accessible regardless of geographic location and facilitate long-term contact. A structured search of Medline, EMBASE, CINAHL, and PsychINFO was conducted for articles published since inception until July 2015. Included studies were randomised controlled trials evaluating complex dietary interventions in adults with chronic disease, delivered predominantly via telehealth methods. A total of 25 studies encompassing 7,384 participants were eligible ranging from two to 48 months duration. The telehealth mode utilised was dominated by the telephone (13 studies), mobile phone (4 studies), internet (3 studies), a video (1 study), videoconferencing (1 study), and 3 studies used a combination of technologies. Overall diet quality was significantly improved by telehealth intervention, improvements ranging from 1.3-3.5 points (SMD 0.22 [95% CI 0.09 to 0.34];p>0.0007). Telehealth intervention also significantly increased the number of fruit and vegetable serves per day by 1.04 serves ([95% CI 0.46, 1.62]; p<0.009), and reduced dietary sodium intake (SMD -0.39 [-0.58, -0.20];p<0.0001). This was paralleled by significant improvements in other measures of dietary intake and translated to reductions in blood pressure and weight, with a pooled estimate showing a clinically meaningful reduction in systolic blood pressure (MD -2.97mmHg ([95% CI -5.72, -0.22];p>0.05) and weight (MD -0.80kg [95% CI -1.61, 0]; p<0.05). Sources of heterogeneity were identified and related to the variability in the technologies, frequency of contact, and chronic disease populations. Telehealth intervention significantly facilitates complex dietary change, specifically diet quality, fruit and vegetables, and dietary sodium intake. This review should guide the development of future evidence-based telehealth programs that can be tailored to specific chronic disease conditions.