Prostate specific antigen, otherwise known as PSA, is a type of protein that is produced from the cells of the prostate gland. Measuring the levels of PSA can determine whether an individual has the possibility of having prostate cancer. This test is usually performed on men ages 50 years or over. If the PSA test shows high levels of prostate specific antigen, this could mean the possibility of cancer, but PSA levels can be increased as a reaction to particular food intake and other reasons.
If a PSA greater than 4 nanograms/ml, further investigation may be required by a urologist. High levels of PSA do not always mean prostate cancer is present. For further information on PSA levels and foods that can help to reduce these levels, see Resources.
A research study was conducted on 1000 men, who all had positive PSA results. Fifty per cent of them were false positives after being retested weeks later. It is now advised that a second test should be administered after a first positive result, as there are many factors that can increase PSA levels. Further information is below.
A study conducted by the San Fransisco VA Medical Center revealed that the omega-6 fatty acids that are usually found in corn oil can increase the growth rate of prostate tumour cells. Yet, soy oil has been proven to decrease prostate cancer levels.
An Australian study that included 29 Australian men with prostate cancer who were waiting to undergo a radical prostatectomy revealed that consumption of high phytoestrogen bread made with 50 grams of soy grits and 20 grams of linseed as well as wheat bread (which is naturally low in phytoestrogens) increased PSA levels between 21.3 and 40 per cent. See "PSA--Good and Bad Foods" below.
Red Meat and Dairy Products
Ajit Varki, MD, conducted research at the University of California, San Diego School of Medicine and revealed that the consumption of red meat and dairy products can contribute to the rise of PSA levels and may contribute to the increased risks of cancerous tumours (see Resources).
Sweets & Desserts
Sweet foods that are high in sugar and calories have been found to decrease the levels of metabolism within the body, therefore creating possible increase of PSA risks and other health factors.