Metabolic syndrome (MS) is characterized by a combination of metabolic risk factors such as abdominal obesity, raised triglycerides, lowered high-density lipoprotein cholesterol (HDL-c), hypertension and impaired glucose tolerance. This study was carried out estimate the effect of dietary lifestyle intervention on some risk factors of metabolic syndrome among selected adult cases. The study was conducted on 140 adults, (20 – 60 years), males and females suffering from one or more of MS risk factors. Dietary and lifestyle intervention (3 months of adequate diet, healthy lifestyle and nutritional education) for 50 cases selected with high risk factors. Anthropometric, laboratory and dietary assessments were made at baseline and at the end of intervention. Results of dietary and lifestyle intervention showed very high significant changes (p < 0.0001) especially for anthropometric measurements of cases (n=50), weight and BMI were decreased by about 13.7 %, waist circumferences, and hip circumferences were reduced by 13%, and 9 % respectively by the endpoint of the intervention period. These changes also lead to laboratory improvement in syndrome indicators like FBG (fasting blood glucose), lipid profiles (TC (total cholesterol), TG (triglyceride), LDL-c (low-density lipoprotein cholesterol), and HDL-c). Conclusion: Diet and lifestyle modifications are the first line of treatment in dealing with MS. Decreasing about 10% of body weight is very useful for preventing or reducing metabolic syndrome risk factors and its complications among adults. Recommendation: balanced caloric intake and physical activity to achieve and maintain a healthy body weight as possible are essential.