In general, foods that are high in protein, fat and sugar are acid-producing. These include meats, seafood, fish, poultry, dairy, and grains. Foods producing an alkaline environment after being metabolized by the body are mostly fruits, vegetables, lentils, seeds, sprouts, roots, and tubers.
The typical American diet is high in protein foods, fats and sugar, and low in fruits and vegetables. This type of diet requires buffers to raise the acidic pH to greater than 7.0, so that the body functions appropriately. But there is a price to pay. After using up its excess potassium and sodium reserves, then calcium, magnesium and other important minerals are used as buffering agents. Since 99% of our calcium stores reside in our skeletal structure, it is our bones that must make the sacrifice. Therefore, regular over-consumption of acid-producing foods ultimately results in bone mineral loss. This can lead to osteoporosis (weak, calcium-depleted bones) and increase our risk of bone fracture.
National surveys reveal that children are drinking twice as much soda as milk (thirty years ago it was just the opposite). This has dire consequences for the future of young bones. And bone health will not only suffer because they drink less milk than in the past. The risk of osteoporosis will be increased by the acidic environment created from the phosphorous in the sodas. Too much phosphorus raises the acid environment of the body and requires buffers. Again, when the stores of buffering agents, especially potassium and sodium, are diminished, the body’s bones will be called upon to give up some of its calcium foundation, weakening the bones during the final period of life when bone matrix can be built and strengthened by diet (adolescence/early adulthood).
There are many reasons to eat a diet predominately plant food, with moderate amounts of fish, poultry, and limited amounts of red and processed meat. Preventing heart disease, stroke, many types of cancer and other chronic conditions are but a few. Maintaining an appropriate acid-base balance is another. Here are some general nutritional guidelines for keeping the acid-base balance where it needs to be:
- Get more protein from plant foods (e.g. lentils, seeds, nuts, tubers). They do not leave the “acidic footprint” that protein from animal sources do. We can still consume animal-derived protein, but in moderation and by choosing carefully. Low-fat dairy products contribute to the acid environment – but not as badly as other animal products such as beef – plus we need the calcium and other nutrients. Yogurt is a good dairy choice for calcium, and is a low-acid-producing food. Also, you’ll want to take the American Heart Association’s recommendation on eating cold-water fish (e.g. tuna, salmon, mackerel, sardines) a couple of times a week to get healthy omega-3 fats.
- Stay clear of processed foods, particularly flour. Processed flour is among the foods that create the highest acidic effect in the body.
- Limit fatty foods, as many fats turn acidic once digested. Choose olive oil for use in cooking, to mix with salad dressing or as a bread dip. Olive oil has a neutral effect on acidity. Next best common oils are canola and sunflower, as they are close to neutral as well. (The same goes for avocado oil, so green light for all you guacamole lovers!)
- Limit concentrated sweets. If using sweeteners, consider honey or brown sugar, as they end up contributing to the alkaline side of the acid-base balance.
The resulting diet is basically the same as is recommended by most dietitians. Eat a plant-based diet with plenty of fruits and vegetables, moderate amounts of low-fat or fat-free dairy products, limited amounts of animal protein and avoid processed foods as much as possible.
Sources: Journal of Nutrition. June 1, 1998, Vol. 128, No. 6, 1051-53.
International Journal of Integrative Medicine, Vol. 2, No. 6, Nov/Dec 2000