Tomato Consumption and High Density Lipoprotein-cholesterol
Condition: Hypoalphalipoproteinemia
MeSH terms: Hypoalphalipoproteinemias
Study type: Interventional

Summary: 
      -  This is a randomized, open-label, single blind, clinical trial

        -  The study evaluated the effect of tomato consumption in serum HDL-cholesterol levels.

        -  The hypothesis was that two daily tomatoes during one month will increase the HDL-c
           levels.

        -  Since a placebo of tomatoes cannot be done, the control group will receive same
           proportion of cucumber because 1) it was not possible to have a tomato placebo; 2)
           cucumber does not have any lycopene; 3) both can be prepared similarly; and 4) the
           required quantity can be measured in the same way.

        -  The intervention was during 1 month and was assigned by randomization.

        -  Personnel who did the clinical and biochemical evaluation were blinded for the
           intervention.

        -  Lipid profile was measured before and after the intervention.

        -  Confounding factors such as daily physical activity, diet, consumption of fish or
           alcoholic beverages, smoking status were considered during statistical analyses.
    

Detailed description: 
      Cardiovascular disease (CVD) is a main cause of death worldwide (1) and there are well
      recognized risk factors associated with its development. Low high density
      lipoprotein-cholesterol (HDL-c) rank among the most common lipid abnormalities associated
      with CVD (2). Low HDL-c is currently defined as an HDL-c value below 40 mg/dL for men and
      below 50 mg/dL for women (3). Factors related with low HDL-c are cigarette smoking (4), high
      triglycerides (5), sedentary lifestyle (6), and insulin resistance (7). Non-pharmacologic
      strategies to increase HDL-c concentration are increasing alcohol (8) and fish consumption
      (9), weight reduction (3), increment in physical activity (10), and smoking cessation (8).
      Some of these strategies are not applicable or hard to implement in individuals affected with
      low HDL-c. Moreover, in low-income countries, these interventions could be costly for the
      general population. Vegetables consumption could be a more affordable and accessible option
      to treat low HDL-c. Epidemiologic evidence indicates that high consumption of vegetables
      reduces the risk of cardiovascular disease (11) and particular attention has received
      tomato-based products. Growing evidence from several epidemiological studies has indicated
      that lycopene, the major carotenoid in tomato (12), might be more important than other
      carotenoids in preventing atherosclerosis and CVD (13, 14). The consumption of more than 7
      servings per week of tomato-based products has been associated with a 30% reduction in the
      relative risk of CVD (15). Such potential benefits to vascular health from a tomato-rich diet
      could be related to low arterial intimal wall thickness (13, 16), reduction of LDL
      cholesterol levels (17), and inverse correlation with markers of inflammation and vascular
      endothelial dysfunction (18). However, HDL-c levels could also be positively influenced by
      tomato consumption. In a pilot study we found that tomato juice consumption did not increase
      HDL-c after one month (unpublished data), this finding also was recently reported by another
      group (19). In contrast, other study showed that daily consumption of 300g of uncooked
      tomatoes, during one month significantly increased HDL-c levels by 15.2% (20). However, this
      study was not controlled, not blinded, and neither randomized. Roma tomatoes consumption
      could be an accessible intervention to improve HDL-c levels; however, a longitudinal clinical
      trial is necessary to evaluate this association. Therefore, we performed a randomized,
      open-label, single blind, clinical trial to specifically evaluate if consumption of two
      uncooked tomatoes per day (14 servings/week) during one month could produce a favorable
      effect on HDL-c.
    

Intervention name(s): Tomato consumption; Cucumber consumption
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): Daily consumption of 300g of uncooked roma tomatoes during one month.; Daily consumption of 300g of cucumber.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: High density lipoprotein cholesterol; Tomato; Lycopene; Hypoalphalipoproteinemia; Dyslipidemia