Is glutamate unhealthy?

What is glutamate?

Most people probably know glutamate simply as a flavour enhancer in Aromat. But glutamate is much more than just an industrial additive – we can't live without it.

What is glutamate made of?

Glutamates are salts of glutamic acid. This means that they’re found in nature, are non-essential amino acids and, as such, are protein building blocks. They’re produced by the body itself and act as messenger substances in the brain.

Neurotransmitter function – what does glutamate do in the brain?

As a neurotransmitter, glutamate transmits information between nerve cells and thus performs an important function in the body. Information is passed from one cell to the next, for example when we're learning or when we move.

Origin and production of glutamate

Industry uses the salts of L-glutamic acid. The most common industrial additive is monosodium glutamate, also known as E621 or MSG, that spices up the flavours of pizza, soup and crisps. In 1908, Japanese professor Kikunae Ikeda succeeded in extracting precisely this monosodium glutamate from Kombu seaweed. This made him the discoverer of the fifth flavour umami and the flavour-enhancing property of glutamate. Neither sweet, salty, sour or bitter, umami is described as fleshy, spicy or pleasantly tasty.

Industrial production and additives

How is glutamate produced? Today, glutamate is industrially produced by fermentation and can be found on the list of food additives under the E-substance numbers E620 to E625. The labelling isn't always clear for consumers. Manufacturers often use synonyms that sound more innocuous. For example, glutamate is often referred to as seasoning, flavouring, yeast extract or fermented wheat.

Glutamate in foods

Some foods naturally contain glutamate. This means that when eating a balanced diet we consume approx. 10-20mg glutamate per day.

Foods that contain glutamate

Natural sources of glutamate:

• Tomatoes: Ripe tomatoes in particular contain high amounts of natural glutamate.
• Cheese: Parmesan and other mature cheeses are rich in natural glutamate.
• Mushrooms: Shiitake mushrooms in particular contain a lot of natural glutamate.
• Meat/fish: In general, protein-rich foods contain a lot of glutamate as it’s a component of most proteins.
• Soy sauce: Due to the fermentation processes, soya sauce is rich in natural glutamate.

Foods with added glutamate (MSG):

• Ready-made soups and stock cubes: MSG is often added to enhance the flavour.
• Spice mixes and spicy sauces: Many commercially available spice mixes contain MSG.
• Fast food and snacks: Fast food meals and snacks such as crisps are often flavoured with MSG.
• Frozen meals: Many frozen meals contain MSG to enhance their flavour.
• Instant noodles: A classic product that often contains MSG.

Glutamate content in mg per 100g food:

• Soy sauce: 1,260mg
• Parmesan: 1,200mg
• Anchovies: 630mg
• Smoked ham: 340mg
• Peas: 200mg
• Tomatoes: 140mg
• Sweetcorn: 110mg
• Potatoes: 30-100mg

Glutamate side effects and intolerances

IIs glutamate unhealthy? It’s primarily the industrial use of glutamate that comes under criticism.

• Chinese restaurant syndrome: It was in the 1970s that the first health concerns were raised in connection with glutamate intolerance, commonly known as the Chinese restaurant syndrome. After eating food containing glutamate in mainly Asian restaurants, many guests experienced symptoms such as headaches, nausea and numbness.
• Toxic effect: Glutamate is said to have a neurotoxic effect, which can lead to diseases such as Alzheimer's and Parkinson's disease.
• Increased appetite: Glutamate plays a role in regulating appetite in the brain. It is said to increase appetite and thus to be partly responsible for obesity.
  

Glutamate intolerance: symptoms

The following symptoms can indicate a glutamate intolerance:

• dry mouth
• headaches
• racing heart
• nausea
• painful limbs
• skin redness
• itching
• numbness
  

From a scientific perspective: Is glutamate harmful to our health?

What is the effect of glutamate? Neither double-blind trials nor the general data picture sufficiently support allegations that glutamate is harmful to our health. Significantly more extensive studies would be necessary to clarify this. National experts therefore agree that glutamate consumed in normal amounts in a balanced diet isn't harmful to our health. It has also not been confirmed that glutamate can trigger allergic reactions. Nevertheless, certain people are glutamate-intolerant.

Therefore: There's no harm provided you eat a balanced diet and consume glutamate in moderation – especially when it comes to ready-made meals. People intolerant to glutamate should avoid it altogether.