Alkaline Diet

Foods that are highly alkalizing are fruits and vegetables. These foodstuffs produce a negative PRAL (Potential Renal Acid Load) rating when the nutritional content is analyzed. For people interested in the alkaline acid diet and optimum pH balance of the body it is worth noting that within this group of alkali producing food, some produce has a more beneficial effect on the body than others. For example, according to the study by Remer and Manz, rasins are one of the most highly alkalizing fruits and spinach is a high alkaline vegetable, both being great for health. We must remember that it is not the amount of acid contained in fresh fruit that determines the acid alkaline balance but rather the pH of the ash after we have burned the food in our bodies.

What I was interested to discover was further details regarding high alkaline foods. There were two parts to this question regarding their health benefits. Firstly what are the highest alkaline fruits and vegetables that we can include in our diets? And secondly what is it about the nutritional content of these foodstuffs that cause them to have a strong base (alkali) forming effect? Knowing what these foods are may be useful in combatting the effects of acid foods.

Using the data from the study Potential renal acid load of foods and its influence on urine pH. the highest alkaline forming fruit, out of those measured, was raisins with a PRAL value of -21.0 while for vegetables the highest was spinach at -14.0. The negative values indicate alkaline forming foods while a positive value would indicate an acid forming potential. The formula that I will be using as the basis for the comparison of the alkaline properties of the fruit and vegetables I mention in this article follows:

For the sake of comparison I shall include the relevant nutritional information for apples, oranges and raisins to see if there are marked differences in any of the nutrients.

Raisins PRAL = 0.49*3.07 (protein) + 0.037*101 (phosphorus) – 0.021*749 (potassium) – 0.026*32 (magnesium) – 0.013*50 (calcium) = -11.9697

Apples PRAL = 0.49*0.26 + 0.037*11 – 0.021*107 – 0.026*5 – 0.013*6 = -1.9206

Oranges PRAL = 0.49*0.70 + 0.037*12 – 0.021*169 – 0.026*10 – 0.013*43 = -3.8897

The nutritional data for these fruits was taken from the United States Department of Agriculture site (see references). This is a great site regardless of what diet you are interested in. It contains details of the nutritional content of a wide variety of foodstuffs. The site makes it possible to determine the PRAL values for any alkaline acidic foods we are interested in. Using the PRAL Calculator that my brother wrote for me, you can check the Potential Renal Acid Load of any food you want. As can be seen from the figures above, even though raisins have higher levels of protein they also have much more potassium. This seems to be what accounts for the large negative value and therefore the highly alkalising effect they are reported as having. So a simple option to consider for those wanting to combat the effects of an acidic forming diet would be to eat more fruits in general but in particular, raisins.

One of the main goals for people interested in the alkaline acid diet who want health is to alkalize by eating healthy quantities of acid and alkaline ash foods. We must also remember that incorporating exercise into our lifestyle is an essential part to becoming healthier overall. Being aware of the high alkaline foods such as those discussed in this article offer ways to get an extra alkali kick.

References: USDA National Nutrient Database

Thomas Remer, Triantafillia Dimitriou and Friedrich Manz Dietary potential renal acid load and renal net acid excretion in healthy, free-living children and adolescents American Journal of Clinical Nutrition, Vol. 77, No. 5, 1255-1260, May 2003

The conflicting information available online about the alkaline acid diet means that you might have difficulty determining whether coffee is an alkaline food or an acid food. Despite the fact that I originally believed it was an acid food and actually decided to stop drinking coffee based on various alkaline acid food charts I had seen, I now believe that rather than having an acidifying effect upon our bodies, it actually has a mildly alkalizing effect.

But is coffee acid or alkaline? The alkaline acid diet has much to teach us about the effects various foods have upon our bodies. However my opinion is that it is rather absolute to base your dietary decisions solely on whether a particular food is an acid or alkaline food. For example, other than their alkalizing effect upon our bodies, there are many other reasons why we should eat sufficient fruit and vegetables. Conversely, even though egg yolks have a strongly acidifying effect upon our bodies, they are full of nutrients. So eating acid foods isn’t necessarily a bad thing.

The premise of the alkaline acid diet, that eating alkaline and acid foods in a ratio between 70:30 to 80:20 alkaline to acid allows our bodies to remain in the best pH balance is appealing. However it acan be frustrating when you see a food appear on the acid foods side on some charts while being on the alkaline foods side of others. Which is it? Is coffee acid or alkaline?

The reason I now consider coffee to be an acid food is  because of the charts that list it as such. While many of the “popular” charts suggest it is acidic, or even highly acidic, the charts that actually provide scientific references for their data, as well as the seminal research by Remer and Manz say that it has a mildly alkalizing effect. However most pop food charts don’t provide any reference as to where their data is from.

There are other arguements both for and against drinking coffee. Looking into green coffee beans may be an option for the health conscious to consider. From the available research I feel confident that as far as the alkaline acid diet is concerned, coffee is actually an alkaline food.

Reference: Remer T, Manz F. Potential renal acid load of foods and its influence on urine pH. J Am Diet Assoc 1995;95:791