A natural way to cardiovascular health

The article by Dauchet et al. (Fruits, vegetables and coronary heart disease. Nat. Rev. Cardiol. 6, 599–608; 2009),¹ which reviews the available evidence for the cardioprotective potential of fruits and vegetables, highlights the importance of healthy foods and a balanced diet. This topic interests many researchers around the world who have spent time and effort demonstrating the efficacy of fruits and vegetables in the prevention of cardiovascular diseases and many other chronic conditions.

Fruits and vegetables have been consumed all over the world for centuries, both as food and as a cure for diseases.² They generally form part of an individual's normal diet, and are also prescribed by healers practicing traditional medicine. The Mediterranean diet, which mainly constitutes fresh fruits and vegetables, has been shown to be cardioprotective;³ although, as pointed out by Dauchet and colleagues,¹ there are other healthy components of this diet and so the benefits cannot be attributed to fruits and vegetables alone.

The consumption of fruits and vegetables for preventing cardiovascular diseases is advocated in a number of traditional systems of medicine; one example is the Canadian Aboriginal system (Table 1).^4,5,6 To get the best results from natural health products (NHPs), it is important that they are used correctly, including selecting the right plant, in the right season, and preparing it in the desired form (such as an infusion) either alone or in combination with other NHPs. The action of NHPs depends upon the balance between multiple compounds, which often have conflicting mechanisms, to give a final therapeutic effect.

Table 1 Cardioprotective fruits and vegetables used in Canadian Aboriginal medicine^4,5,6

In order to incorporate the use of fruits and vegetables as complementary therapies into mainstream medicine, more high-quality basic and clinical research is needed. We have reported the cardioprotective activities of various traditionally-used fruits and vegetables such as betel nut,^7,8 ginger,^9,10 carom/ajowan,¹¹ radish,¹² and peony.¹³ In addition to evaluating these plants pharmacologically, chemically, and toxicologically (Table 2), we have also shown that most of these and other NHPs are more active on hyperactive, rather than resting, tissue preparations;^9,10,12,13 this finding is also mentioned by Dauchet et al.¹

Table 2 Cardioprotective NHPs evaluated pharmacologically, chemically and toxicologically^*‡

Most importantly, more randomized controlled trials investigating the effects of NHPs are needed. Conducting these studies is costly, and securing the required funds for NHP trials is difficult, although alternative strategies are available.¹⁴ Active participation from the medical community will be helpful. Throughout the history of medicine, physician–scientists have been instrumental in the area of ethnopharmacology and clinical use of NHPs.¹⁵ There is a need for physicians to be trained, right from their initial years at medical school, in the various forms of complementary therapy. This would equip physicians with an additional therapeutic tool and will help prevent problems like inadvertent adverse drug–herb interactions. It will also give patients the confidence to let a trained physician know of their alternative therapy use. Fruits and vegetables have been used medicinally through the ages, but the road toward gathering the evidence needed for their definitive use is still long.