What Is Lactic Acid?

Lactic acid is one of those terms you hear a lot when learning about healthy lifestyles. From fermented foods to fitness, this particular acid plays a very important role in our lives, but is hardly ever explained in detail.

So what exactly is lactic acid and what does it do to (and for) us?

Lactic acid is, as the name suggests, a type of acid that often has a colourless, syrupy quality when separated from other elements. On a more scientific level, it’s described as an organic chemical that’s formed “when sugars are broken down for energy in the absence of adequate oxygen”.

For humans, it’s one of the main anaerobic (without oxygen) processes used to convert fuel to energy. So when we do intense exercise, for example, our bodies will break down carbohydrates and produce lactic acid, which is what creates the burning sensation you feel when you lift weights, go for a run, do laps at the pool and so on. The lactic acid (or lactate) that’s produced is then used for energy.

Lactic acid is also produced as part of the fermentation process for many foods and drinks, including cheese, sourdough bread, yoghurt, kefir, kombucha, sauerkraut, kimchi, and pickled vegetables and meats.

The bacteria involved in the fermentation process – including probiotics such as Streptococcus thermophilus and Lactobacillus bulgaricus – eats the sugars found in them and produces lactic acid. The acid then becomes part of the fermentation and preservation process, giving these foods their distinct tanginess.

Just as lactic acid in our muscles is important for providing fuel and improving fitness levels, lactic acid in food has been linked to a range of health benefits, including:

• Improved nutritional value of food,
• Control of intestinal infections,
• Improved digestion of lactose,
• Control of some types of cancer; and
• Control of serum cholesterol levels

The US National Institute of Health says that some of these benefits may be the result of the fermentation process, while others could be because of how the bacteria in these foods positively affects our gut health when we eat them.

Although lactic acid on its own doesn’t provide all the health benefits we hear about when it comes to working out or eating healthy foods, the connection it has to these things is very clear. So basically, lactic acid is another piece of the puzzle that’s needed for us to achieve and sustain healthy lives through fitness and food.