Overweight and obese hypertensive patients can greatly benefit from high adherence rates for lifestyle modifications. The objectives of this paper were to investigate how patients' weight status affected physicians' recommendations of lifestyle modifications and patients' adherence after they received the recommendations. The patients were adults (18+ years of age) with hypertension (prehypertension, Stage I and Stage II hypertension). The National Health and Nutrition Examination Survey (NHANES) 1999-2000 was used. Weight status was categorized as normal/underweight, overweight and obese. Physicians' recommendations of and patients' adherence to lifestyle modifications (weight control, exercise, sodium intake reduction, alcohol intake reduction) were examined using descriptive and multivariate analyses, controlling for weight status, hypertension stage, comorbidities and demographic characteristics. About 57.0% of the US adult population in 1999-2000 had prehypertension, Stages I or II hypertension. Among the hypertensive adults, 30.3% were normal/underweight, 32.6% were overweight and 37.2% were obese. We found that physicians were more aggressive in recommending lifestyle modification for obese patients. In contrast, obese hypertensive patients were not found to be more likely than normal/underweight patients to adhere to lifestyle modification recommendations. In addition, adherence rates for sodium and alcohol consumption reduction were higher than that for either exercise or weight control. In conclusion, more aggressive approaches should be taken by physicians to educate obese patients about the benefits of lifestyle modifications and to improve adherence to enhance the effects of antihypertensive medications.