Miracle fruit (Synsepalum dulcificum) contains the glycoprotein miraculin, which provides potential sweetening and taste-modifying effects. When consumed before acidic foods (pH < 6.5), miraculin binds to human sweet taste receptors, generating a temporary perception of sweetness(1). This effect is predominantly studied on sour taste. As informed by our narrative review(2), its effects on other tastes and the impact of miracle fruit doses across all tastes remain underexplored. This pre-post quasi-experimental pilot study aimed to investigate the effects of selected miracle fruit doses (175 mg, 350 mg, 700 mg) on solutions and foods representing different tastes. We hypothesize that miracle fruit decreases the perceived intensities of sourness, tartness, and bitterness while enhancing the sweetness, and seek to establish the optimal dose for future dietary interventions. Ethical approval was obtained from Griffith University Human Research Ethics Committee (2024/052). Forty-five healthy Australian adults of a median age of 22 (20.0-26.0) years and BMI of 22.5 (21.5-23.9) kg/m2 rated the taste intensities of solutions and foods on general Labeled Magnitude Scales from 0-100, before and after consuming miracle fruit tablets of a given dose. Non-acidic solutions and foods were acidified using citric acid and lime juice, respectively, to activate miraculin(3). Socio-demographic data, body composition, saliva pH, and bitter taste sensitivity (TAS2R38 genotype and phenylthiocarbamide response) were recorded as potential covariates. Data were analysed using SPSS 29.0. Generalized linear mixed models examined the effect of dose on taste intensities, after adjusting for covariates (age, sex, phenylthiocarbamide response) and participant variability. The low dose (175 mg) was suitable to significantly decrease the sourness of citric acid solution [β = -1.331, 95% CI = (-1.811, -0.850), p < 0.001], lime [β = -1.177, 95% CI = (-1.519, -0.835), p< 0.001], and bitterness of broccoli [β = -0.674, 95% CI = (-1.091, -0.258), p = 0.002], and enhance the sweetness of sucrose solution [β = 0.433, 95% CI = (0.170, 0.695), p = 0.002] and maple syrup [β = 0.413, 95% CI = (0.152, 0.674), p = 0.002]. The moderate dose (350 mg) masked the tartness of tartaric acid solution [β = -1.063, 95% CI = (-1.483, -0.643), p < 0.001] and Granny Smith apple [β = -0.661, 95% CI = (-1.126, -0.195), p = 0.006]. Miracle fruit did not change the bitterness of the 6-n-propylthiouracil solution. In conclusion, miracle fruit enhances sweetness and masks sour, tart, and bitter tastes under acidic conditions, with effects varying by miracle fruit dose and food matrix (liquid/ solid). These findings highlight miracle fruit’s potential as a sweetener in future dietary interventions to replace added sugars and support the consumption of sour/tart fruits and bitter vegetables. Furthermore, it can potentially over-sweeten already sweet items to make them less preferable.