Nutrition as Medicine

A lot of health-related companies use Hippocrates quote “Let food be thy medicine and medicine be thy food” to promote their business or products. In the hippocratic collections, the authors often referred to both foods and drugs when describing treatments. In addition, they usually avoided defining the difference between the two categories (1). Nowadays health claims made about food and supplements are strictly controlled by the law. According to the legislation, foods can’t be marketed with medical claims, i.e. claims that food prevents or cures a disease. If such a statement is made, food will be classified as medicine, which are controlled by more strict legislations.


According to the Hippocratic doctors, food was absorbed into the body with the aid of the body’s heat to break it down into the nutrients needed to sustain the body. They also claimed that these foods contained the powers which could nourish the body in several ways. Moreover, Hippocratic doctors supported that foods nourish and drugs produce change, with the second being frequently dried or strengthened forms of plant and animal products in the standard diet. The power of a product thus depended on whether nutrition was the objective, or a more powerful, drug-based, intervention was necessary (2). To fight diseases, Hippocratic doctors used two kinds of Interventions: one based on the previously existing therapeutic interventions including incisions, and cauterization medicines. The second one was the new regimen or dietetic interventions, which was considered as the most important (3).


Later, in the second century AD, Galen (a physician to Emperor Marcus Aurelius) reported that items of diet might have drug-based rather than strictly nutritional outcomes (2). In Medieval Europe, doctors used Asian spices such as ginger, black pepper, and cinnamon not only for improving food taste but mainly for their ‘hot and dry’ properties which they believed that could help rebalance the ‘cold and wet’ European diet and promote health.


In Asia, historically the highest-ranking doctor in Chinese medicine, was the diet doctor. Okinawans who live between Japan and China, have been strongly influenced by Chinese ideas of longevity achieved through diet. They believe that ‘food makes the man’ and that the food they eat is medicine for life. They support that certain foods have many medicinal qualities linked to longevity. According to many studies, Okinawan people are one of the longest living people in the world.


Food as Medicine - Current Data


Food as a Disease Risk Factor


According to the Food and Agriculture Organization of the United Nations, in 2014-2016 around 795 million people are chronically undernourished without access to adequate amounts of food for basic good health. This fact confirms that food is scarce and poverty and associated ill health remains a significant global public health issue (4).


On the other hand, in many countries, the obesity epidemic is a serious public health issue. Modern societies could be characterized as supporters of unhealthful eating patterns and sedentary behavior and any obesity prevention and treatment attempts resulted to limited overall success (5). It is not an exaggeration to say that while Third World countries fight insufficient or deficient diets, the Developed World is fighting against the consequences of excess or unbalanced nutrition leading to obesity, diabetes and other chronic degenerative diseases (6).


The Canadian Public Health services have published the Chronic Disease Risk Factor Atlas that directly associates nutrition with the risk of developing cancer, coronary heart disease, and stroke. Furthermore, diet is considered as a factor that influences the risk of many other conditions, including obesity, hypertension, and diabetes which in turn are related to the risk of other chronic diseases. There is also a correlation between low consumption of fruit and vegetables and the incidence of chronic diseases such as cardiovascular disease (7).


A report of the Food and Agriculture Organization confirms the above findings by informing that “The diets people eat, in all their cultural variety, define to a large extent people’s health, growth, and development.” This report also emphasizes that both undernutrition and overnutrition play a role in the development of chronic disease (8).


Another study (2008) concluded that there are food patterns that are related to obesity and obesity-related cardiovascular disease risk factors (9). Additionally, a recently published study (2018) has found that diet and dietary patterns are associated with blood pressure and hypertension (10).


Food and Disease Prevention


The importance of food in the prevention of disease is confirmed by a large body of evidence. The risk of cardiovascular diseases such as heart disease and stroke can be reduced by eating less saturated and trans fats, and sufficient amounts of polyunsaturated fats, fruits and vegetables accompanied by decreased salt consumption (11). High salt intake has shown to contribute to elevated blood pressure, a major risk factor for not only cardiovascular diseases, but also many other non-communicable diseases.


Furthermore, there are studies reporting evidence of a protective effect of fruits and vegetables against forms of cancer such as esophageal cancer (14). A more recent study (2018) suggests that increased higher consumption of cruciferous vegetables reduces the risk of colorectal and gastric cancers by approximately 8% and 19% respectively (15).


Since 1998, grain products in the United States have been fortified with folic acid to reduce folate deficiency, a major contributor to neural tube defects during pregnancy (12). Since then, the rates of neural tube defect pregnancies have declined by about 19 percent. In addition to food fortifications, governmental bodies have started to take more initiative in educating consumers about food and its health effects, while encouraging food companies to make products that are more nutritious (13).


Food as Medicine?


Studies have shown that diets rich in fiber contribute to cholesterol levels. The European Food Authority (EFSA) has approved that a health claim stating “Regular consumption of beta-glucans contributes to maintenance of normal blood cholesterol concentrations.” can be used for products containing beta-glucan, a soluble fiber that can be found from oat and barley (16). It has also been suggested that increasing fiber intake can lead to a 10% reduction in LDL-cholesterol (17). Thus, it is important to consume fruits, vegetables, legumes and whole grain cereals. Of course, a reduction of this magnitude is only sufficient for those whose levels are at the borderline of normal. For the patients in need of a 50 or even 100% reduction, an increase in fiber intake alone is not sufficient to replace prescribed medicine.


However, food can play a supplementary role: i.e. the consumption of foods fortified with plant sterols (plant derived sterols that inhibit absorption of cholesterol from the small intestine) together with cholesterol lowering drugs shows an additive effect on the reduction of total cholesterol and LDL-cholesterol levels (18). The additive effect of food has also been observed among cancer patients (19). Improved outcomes were observed when supplementing with omega-3 fatty acids during chemotherapy in metastatic breast cancer patients. As these studies show, with serious health conditions, food cannot be taken on its own as medicine but can improve the overall treatment outcomes.


Recently also type 2 diabetes and its relationship with food has been a topic for discussion. Although some studies confirm that weight-loss may eliminate type 2 diabetes, there are no drugs that can have such a significant result. However, it is a whole lifestyle modification including exercise, changing eating habits and controlling emotions that leads to successful diabetes management or elimination. Even in this case when food can be used to cure or improve management of a disease, one food alone cannot help. Thus we cannot say that a specific food treats type 2 diabetes and can replace drugs. Besides, until the patient reaches a state where diabetes doesn’t exist anymore, he must continue taking his anti-diabetic pills.


Take away message


Although we can talk about the benefits of single foods, we must highlight that these foods combine into a complex diet. The addition of any so-called ‘superfood’ isn’t going to correct the overall balance of a poor-quality diet. Nutrients in single foods, when eaten together in a meal, will interact. Their consumption might result in a synergistic action that multiplies the beneficial effect. Therefore, when considering food as medicine we need to target a variety of nutrient-rich foods that are components of a diverse and healthy diet.


In other words, a single food alone, may not be marketed and used as a medicine, but overall dietary patterns can have a major impact when treating conditions and disease. As a science, nutrition should be more integrated with today’s medical practice. Dietary advice should be given hand in hand with modern medical treatment to improve outcomes. That is why we believe and argue that nutrition is medicine.


Published on April 24th, 2018

References


1) Totelin, L. (2015). When foods become remedies in ancient Greece: The curious case of garlic and other substances. Journal of Ethnopharmacology, 167, pp.30-37.

2) Wilkins, J. (2015). Good food and bad: Nutritional and pleasurable eating in ancient Greece. Journal of Ethnopharmacology, 167, pp.7-10.

3) Cardenas, D. (2013). Let not thy food be confused with thy medicine: The Hippocratic misquotation. e-SPEN Journal, 8(6), pp.e260-e262.

4)  Food and Agriculture Organization of the United Nations. (2017). How close are we to #ZeroHunger? The state of food security and nutrition in the world. (Accessed: April 2018). Available at: http://www.fao.org/state-of-food-security-nutrition/en/

5) Lake, A. (2018). Neighbourhood food environments: food choice, foodscapes and planning for health. Proceedings of the Nutrition Society, pp.1-8.

6) Fara, G. (2015). Nutrition between sustainability and quality. Ann Ig., 27(5), pp.693-704.

7) Chronic disease Risk Factor Atlas. (Accessed: April 2018). Available at: https://www.canada.ca/en/public-health/services/chronic-diseases/risk-factor-atlas.html

8) World Health Organization. (2003). Diet, Nutrition and the Prevention of Chronic Diseases WHO technical report series; 916. (Accessed: April 2018). Available at: http://www.fao.org/docrep/005/ac911e/ac911e06.htm

9) Berg, C., Lappas, G., Strandhagen, E., Wolk, A., Torén, K., Rosengren, A., Aires, N., Thelle, D. and Lissner, L. (2008). Food patterns and cardiovascular disease risk factors: The Swedish INTERGENE research program. The American Journal of Clinical Nutrition, 88(2), pp.289-297.

10) Monge, A., Lajous, M., Ortiz-Panozo, E., Rodríguez, B., Góngora, J. and López-Ridaura, R. (2018). Western and Modern Mexican dietary patterns are directly associated with incident hypertension in Mexican women: a prospective follow-up study. Nutrition Journal, 17(1).

11) World Health Organization. (2002). Diet, nutrition and the prevention of chronic diseases. Report of the joint WHO/FAO expert consultation. WHO Technical Report Series, No. 916 (Accessed: April 2018). Available at:

http://www.who.int/dietphysicalactivity/publications/trs916/summary/en/

12) Bank, W., World Bank and Jamison, D. (2006). Disease Control Priorities in Developing Countries. Washington: World Bank Publications.

13) https://www.cnbc.com/2018/03/29/fda-to-consider-updating-health-claims-food-manufacturers-can-make.html (Accessed: April 2018).

14) Berretta, M. (2012). The role of nutrition in the development of esophageal cancer what do we know. Frontiers in Bioscience, E4(1), pp.351-357.

15) Johnson, I. (2018). Cruciferous Vegetables and Risk of Cancers of the Gastrointestinal Tract. Molecular Nutrition & Food Research, pp.1701000.

16) European Food Safety Authority. (2009). Scientific Opinion on the substantiation of health claims related to beta-glucans and maintenance of normal blood cholesterol concentrations, and maintenance or achievement of a normal body weight. EFSA Journal 7(9) (Accessed: April 2018). Available at: https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2009.1254

17) Riccardi, G., Vaccaro, O., Costabile, G. and Rivellese, A. (2016). How Well Can We Control Dyslipidemias Through Lifestyle Modifications?. Current Cardiology Reports, 18(7).

18) Barbagallo, C., Cefalù, A., Noto, D. and Averna, M. (2015). Role of Nutraceuticals in Hypolipidemic Therapy. Frontiers in Cardiovascular Medicine, 2.

19) Fabian, C., Kimler, B. and Hursting, S. (2015). Omega-3 fatty acids for breast cancer prevention and survivorship. Breast Cancer Research, 17(1).