Does MSG cause headaches?

Large-scale controlled studies have not found a consistent link between MSG and headaches at normal dietary levels. The original "Chinese restaurant syndrome" claims from the 1960s have not been replicated in rigorous scientific research. Some individuals may be sensitive to very large doses, but this is rare.

Is MSG worse than salt?

MSG actually contains about one-third the sodium of table salt. Some food manufacturers use MSG to reduce overall sodium content while maintaining flavour. However, MSG is typically found in highly processed foods that may also be high in salt, sugar, and fat.

Glutamate occurs naturally in many foods (tomatoes, cheese, mushrooms). However, the MSG added to processed foods is industrially manufactured through bacterial fermentation. It's chemically identical to natural glutamate, but its use as an additive is a hallmark of industrial food processing.

Flavour Enhancer

What is E621? (Food Additive Explained)

E621 is monosodium glutamate, better known as MSG. It's a flavour enhancer that intensifies savoury (umami) taste in foods like crisps, instant noodles, ready meals, and seasoning mixes. It's one of the most debated food additives, but is approved as safe worldwide.

What is E621?

Full name: Monosodium Glutamate (MSG)

E621 is the sodium salt of glutamic acid — an amino acid that occurs naturally in many foods including tomatoes, parmesan cheese, soy sauce, and mushrooms. As a food additive, MSG is produced industrially through bacterial fermentation (similar to how yoghurt or vinegar is made). It was first isolated in 1908 by Japanese chemist Kikunae Ikeda, who identified it as the source of the "umami" (savoury) taste in kombu seaweed.

What does E621 do in food?

E621 enhances the savoury flavour of food without adding a distinct flavour of its own. It works by stimulating glutamate receptors on the tongue, making food taste richer, meatier, and more satisfying. This is why it's widely used in savoury snacks, soups, sauces, and ready meals — it makes cheaper ingredients taste more flavourful. It is also used to reduce sodium (salt) content while maintaining taste.

Where is E621 found?

E621 is commonly found in:

Crisps and savoury snacks
Instant noodles and cup soups
Ready meals and frozen foods
Stock cubes and gravy granules
Seasoning mixes and spice blends
Chinese and Asian takeaway food

Is E621 bad for you?

Despite decades of controversy, major food safety authorities — including EFSA, the FDA, and the WHO — consider MSG safe for the general population. The idea of "Chinese restaurant syndrome" (headaches, flushing) has been largely debunked by controlled studies. That said, some individuals may be sensitive to large doses. MSG is not toxic, carcinogenic, or allergenic. However, like E471, its presence almost always indicates a highly processed product designed to enhance palatability cheaply.

Why E621 matters for food choices

E621 is a strong marker of ultra-processed food. Under the NOVA classification, flavour enhancers like MSG are industrial additives that are characteristic of NOVA Group 4 products. Their purpose is to make foods hyper-palatable — more rewarding to eat than their base ingredients would normally be. While MSG itself isn't harmful, its presence often signals a product engineered for taste rather than nutrition. Checking for flavour enhancers is one of the fastest ways to spot ultra-processed foods.

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