Libby Ruwitch

Susan Saukas

Deanna Spracher


Student Project Abstract


            We tested the short-term effects of organic food compared to non-organic food on blood pressure and pulse. Farming practices decide whether a food is labeled as organic or non-organic. The main difference in organic versus non-organic food can be found in the fertilizers, pesticides, herbicides and livestock.

Organic foods are grown without any chemicals; instead, the farmers use natural compost to fertilize the plants and they disrupt the mating patterns of insects to keep them away. The farmers also pull up the weeds by hand and feed the livestock a balanced organic diet.  Non-organic livestock are given antibiotics and growth hormones to prevent disease, where as organic practices use rotational grazing and an organic diet to prevent disease.  The overreaching goal of organic farming practices are to limit exposure to hormones, pesticides, and antibiotics. We hypothesize that organic food contains less chemicals than non-organic food, and as a result, the people who consume organic food will have lower blood pressure and pulse.

            We took the participants’ blood pressures and pulses before eating a blind sample of organic or non-organic food, and again 10 minutes after consumption. We tested a range of organic and non-organic food types: cookies, bread, apples, and turkey sandwich meat. We used time and type of food as the independent variables. The changes in blood pressure and pulse were the dependent variables. The controlled variables were the time in between measurements (10 minutes), the activity level (sitting) in between measurements and the amount of food sample the participants consumed during the experiment. The control group consisted of 12 participants that did not consume any food. A total of 24 participants made up the experimental group: 12 consumed organic food and 12 consumed non-organic food. We predicted that if someone consumes organic food, then his or her blood pressure and pulse would decrease.

The trends in data showed that on average blood pressure decreased in participants for all experimental groups, but that the control and organic groups showed the greatest decrease.  For pulse, all groups on average had an increase with the inorganic experimental group with the highest pulse increase.  Three t-tests were run on the data collected for each blood pressure and pulse; The t-tests compared control vs. organic, control vs. non-organic and organic vs. non-organic. In the control vs. organic t-tests the blood pressure resulted in a P value of 0.65 and the pulse had a P value of  0.77.   In the control vs. non-organic t-tests, the blood pressure t-test produced a P value of 0.14 and the pulse had a P value of 0.74. In the organic vs. non-organic t-tests, the blood pressure finding was a P value of 0.54 and the pulse’s P value  was 0.66. None of the results proved to be statistically significant, exhibiting that there is no correlation to a change in blood pressure or pulse between organic and non-organic food in the 10-minute time frame that we used.

            Organic food does not significantly affect blood pressure or pulse compared to non-organic food 10 minutes after consumption, allowing rejection of our active hypothesis. Several factors could have affected our results. The inability to control activity level and food consumption of the participants prior to testing could have affected participants’ blood pressures and pulses. In addition, some participants displayed anxiety about getting their blood pressures taken, which also could have skewed data results. Measuring blood glucose levels before and after organic or non-organic food consumption may be a more effective way of assessing the health benefits of eating organic foods.  Another  approach would be to test the long term effects of organic versus non-organic food on blood pressure and pulse with a larger experimental sample size.