What to Know About Acidic Foods?

Medically Reviewed by Christine Mikstas, RD, LD on February 25, 2024
3 min read

The pH scale is used to measure acidity and alkalinity levels. It measures the presence of positively and negatively charged hydrogen ions in a particular solution. The higher the hydrogen ions, the higher the acidity.

Acidic foods are those that typically have a pH level of 4.6 or lower. High acidic foods are less likely to develop a quick microorganism growth, which means they might take longer to decompose.

The average pH of the human body is about 7.40. This level is perfect for maintaining the body's biological processes. One of the most important functions it regulates is blood oxygenation.

Although there's no conclusive evidence that it helps keep optimal pH levels, many opt to steer clear from foods that cause more acidity in the body. Their main goal is to keep their potential renal acid load (PRAL) within acceptable limits. The PRAL refers to how much acid your body produces when eating certain foods.

Some examples of acidic foods to avoid are: 

  • Fresh and processed meats
  • Eggs
  • Beans
  • Oilseeds
  • Salt
  • High-sodium condiments
  • Some types of cheese
  • Certain grains

People who drink alkaline water, on the other hand, have shown a lower risk of having coronary heart disease and cardiovascular anomalies. A study shows that they also have reduced chances of getting cancer and have low mortality rates.

Studies suggest that a constant disruption in the acid-base balance causes chronic metabolic acidosis. Such continuous high acidity in the body could cause a predisposition to some diseases in the long run. ‌

Acidic foods and urine. An acidic diet will affect the pH levels in your urine. Eating too many animal proteins and drinking too many sweet, carbonated drinks can produce uric acid stones, which are a type of stones that form in your kidneys.

Acidic foods and blood. Researchers typically state that higher or lower consumption of acidic or alkaline foods rarely has any impact on blood pH levels. When there are high acid levels in the blood, it's usually because of underlying conditions like diabetes or kidney problems. Lung disease can be another culprit, as it reduces blood oxygenation.

Acidic foods and the bones and muscles. There was a recurring hypothesis that a higher intake of animal protein was directly linked with osteoporosis. Still, research on alkalinizing diets hasn't proved any effects on bone strength. Numerous studies have shown that acid-base variations in human urine have no impact on one's calcium balance, risk of fractures, or bone metabolism.

Still, phosphoric acid, which is present in some carbonated drinks, is often associated with lower bone density. Researchers claim that dark sodas, which are highly acidic, are to blame for bone density problems when they substitute high protein drinks in a regular diet.

Consuming high acidity foods within reason is part of a healthy and balanced diet. Nutritionists recommend eating a vast amount of fruits and vegetables daily. These foods, although sometimes acidic, have alkalinizing factors that are unlikely to have a negative impact on muscle mass or increase the risks of bone loss.

Some fruits and vegetables with negative PRAL levels that can be beneficial for your health include:

  • cucumber (-2.0)
  • radish (-4.7)
  • limes (-0.4)
  • plums (-1.7)
  • green grapes (-2.4)
  • purple grapes (-1.9)
  • pomegranates (-8.1)
  • blueberries (-0.6)
  • kale (-2.6)
  • raw spinach (-1.5)
  • pineapples (-1.1)
  • apples (-1.8)
  • arugula (-1.1)
  • peaches (-1.5)
  • oranges (-1.6)
  • tomatoes (-1.8)
  • raisins (-9.0)
  • ‌blackberry (-1.0)
  • banana (-5.2)
  • beets (-5.4)
  • cooked shiitake mushrooms (-0.2)

Although okay for consumption for most people, these alkalinizing acidic fruits and vegetables might cause gastric issues in the long run. That's especially true for people who already suffer from acid reflux, heartburn, or a gastric ulcer. If you have any of these problems, ask your doctor before increasing your intake of any of these foods.

Although diets that are lower in acidic foods have no evidence of lowering acidity in the body or having a significant impact on blood, bone, or muscle health, they might help strengthen memory and cognition.

If you want to incorporate alkaline foods into your diet, you can start with:

  • Soy
  • Tofu
  • Tempe
  • Potatoes
  • Herbal teas
  • Lentils
  • Herbal condiments
  • Olive oil
  • Quinoa
  • Amaranth

Unless instructed differently by your doctor, you should always try to keep a balanced diet. Consuming all food groups in moderation is essential for maintaining your body’s health. If you have any concerns that the fruits, vegetables, meats, or dairy that you consume negatively affect your health, seek professional advice. Talk to your nutritionist and ask them if you need to make any dietary adjustments to improve your overall health.