FOOD INTOLERANCE NETWORK FACTSHEET

MSG and the new flavour enhancers

MSG (monosodium glutamate, flavour enhancer E621) summary

• MSG was first introduced into Western food in 1948.

• The first adverse reaction to MSG was reported in 1968.

• A study of 36 healthy volunteers exposed to increasing doses of MSG found that everyone can react to MSG with various symptoms if the dose is high enough.

• The first asthmatic reaction to MSG was reported in 1981 by two Australian doctors.

• Studies carried out by industry-supported researchers and independent researchers have reached opposite conclusions about the safety of MSG.

• A new flavour enhancer introduced into Australia in 1994 can make the flavour enhancing effects of MSG up to 10-15 times stronger.

• Foods labeled NO ADDED MSG often contain new flavour enhancers and/or some natural MSG in the form of yeast extracts or hydrolysed or autolysed plant, vegetable or milk proteins.

The MSG story

MSG occurs naturally in some foods like kombu seaweed, tomatoes and parmesan cheese. It was first isolated in 1908 by a professor at Tokyo University who became a partner in what is now the multi-billion dollar Ajinomoto company which provides more than half the world's MSG. As a concentrate MSG could easily be added to any foods in much greater quantities than in nature.

MSG did not become popular as an ingredient in Western food until after World War II. Noticed as an ingredient in Japanese army rations by US soldiers, it was launched in the USA in 1948 at a symposium in Chicago that was presided over by the Chief Quartermaster of the armed forces. The growing American processed food industry embraced MSG and since then its use has doubled every decade.

At first MSG was used mainly in Asian cooking in relatively large amounts, for example, 3 grams in a bowl of soup in a Chinese restaurant. It is now found in varying doses in virtually all soups, stocks, gravies, sauces, snack foods, takeaway and restaurant meals, including fried chicken and pizza. Flavour sachets in products such as instant noodles and crisps are particularly high in MSG. Although westerners assume MSG consumption is high in Asian countries, estimates of MSG intake in the 90s found higher consumption in the UK than in Japan or Korea. Extreme users - defined as consuming three times the average – had an average at home intake of 16 grams of MSG per week, without even considering snacks and foods consumed outside the home that would clearly be a major source of MSG.

The first reactions to MSG were identified in 1968 by a Dr Robert Kwok who had emigrated from China to the US. Dr Kwok reported that although he never had the problem in China, about 20 minutes into a meal at certain Chinese restaurants, he suffered numbness, tingling, and tightness of the chest that lasted for approximately two hours. This collection of symptoms became known as Chinese Restaurant Syndrome.

A year after Dr Kwok reported his symptoms, researchers in the US found that everyone will react to MSG if the dose is high enough. They also observed that the effect occurred on an empty stomach, which is, of course, how most people eat food. In one study, 36 subjects ate chicken soup with increasing doses of added MSG every day. Half of the subjects reacted to doses between 1.5 and 4.0 grams. Most of the rest reacted to doses between 5 and 12 grams. Researchers commented that it would be possible to prepare a meal containing 10-12 grams of MSG per person if following the manufacturers' recommendations. Although researchers were mainly looking for the traditional Chinese restaurant reactions of burning, facial pressure and chest pain, they also noted migraine, gastric distress and one doctor who admitted himself to hospital, convinced he was having a heart attack – typically, pain in the chest, tingling and numbness from the chest down the left arm and a feeling of impending doom.

Defenders of the faith

In response to the possibility of MSG having toxic potential, a number of associations were organised.

• The International Glutamate Technical Committee (IGTC) consists of doctors and scientists who meet once a year, with a secretariat provided by Ajinomoto, to sponsor MSG research.

• The Glutamate Association was established in 1977 to provide communication and awareness of the ‘use and safety’ of glutamates (www.msgfacts.com).

• The International Glutamate Information Service (IGIS) provides information about glutamates based on ‘scientific evidence which confirms the safety and the benefits of this widely used food ingredient’ (www.glutamate.org). It is supported by the Australian Glutamate Information Service.

Other non-profit organizations that offer science-based information are encouraged to pass on information from the Glutamate Association. An award-winning science website at the University of Texas recommends the International Food information Council (IFIC) website guides. ‘A source of good information,’ it says, while warning that ‘they take a definitely pro-industry stance and tend to gloss over areas of nutritional or food safety debate: for instance, they argue that monosodium glutamate is a perfectly safe food additive.’

Allergists, dietitians and nutritionists appear to have been particularly targeted and glutamate industry involvement is rarely obvious. That's what makes it so effective

Number wars

In 1976 a survey found that 25 per cent of the population experience adverse reactions after a meal in a Chinese restaurant. This study was funded in part by a grant from the National Eye Institute, interested because MSG had been found to cause retinal damage in newborn mice, rats and chicks.

In 1979 a market research questionnaire (commissioned by Ajinomoto) found that less than 2 per cent of the population suffer from Chinese Restaurant Syndrome after a meal. I suspect that this lower figure was achieved because the study did not include reactions that occurred outside a given time limit and narrow symptom range. Soon after this study, the FDA started quoting the figure that only two per cent of the population react to MSG.

The battle for statistical high ground had begun. It is in the food industry's best interests if only a small number of people are seen to react to their product. So when an Australian study about asthmatic reactions to MSG was published, the industry must have felt threatened. A few small industry-funded studies reported no asthmatic reactors to MSG. Then something happened which made it important for them to prove that MSG does not provoke asthma.

MSG goes to court

As an asthmatic, David Livingston knows he reacts to MSG so he avoids it. In July 1993, Livingston went to a Marie Callender’s chain restaurant for a business lunch. He told the waitress he had asthma and wanted to know if the vegetable soup contained MSG. The waitress assured him the soup was ‘made from the freshest ingredients, from scratch … every day’. It was later found to contain a ‘beef base’ that had MSG clearly listed on the label.

On the way back to the office, Livingston felt an asthma attack coming on. When his inhaler failed to provide relief, he drove immediately to his primary care physician, five minutes away. There he suffered an anaphylactic reaction including respiratory arrest. CPR was initiated and continued in an ambulance but after reaching hospital Livingston went into full cardiac arrest and was without pulse for seven minutes. He was finally resuscitated and remained unconscious and on a respirator in the Intensive Care Unit for three days. He remained a further three days in the hospital for observation and treatment. As a result of lack of oxygen, Livingston suffered brain damage and remains with a slight neurological deficit. One year later, David Livingston initiated a lawsuit against Marie Callender’s Inc.

At about the that time, industry-funded researchers Drs Ronald Simon, Donald Stevenson and Katherine Woessner at the Scripps Research Institute and Scripps Clinic began a study supported by the IGTC. As a result, two papers were published that seemed to demolish the idea that MSG could be connected with asthma. Or did they?

Industry and asthma research

Consumer groups first heard of the study when an advertisement appeared in the Los Angeles Times seeking test subjects for a new asthma study at the Scripps. One MSG-sensitive woman who replied was told that ‘1) if she feared her asthma reactions to be serious that she should not apply for the study, 2) that the person who was screening the applicants didn't believe that MSG could cause asthma reactions, and 3) that she was most likely responding to sulfites, and not to MSG’. This was reported in the newsletter of the No MSG group.

I think this is a good illustration of how double blind placebo-controlled (DBPC) studies could be biased, despite DBPC protocols. By rejecting asthmatics who think they react to MSG, can’t you be pretty sure to run a study with no reactors?

The study tested 100 asthmatic subjects (30 subjects with ‘a history of Oriental restaurant asthma attacks’ and 70 with a negative history). There were no signs or symptoms of asthma related to MSG.

However, there is a question mark over the selection of subjects and absence of evidence is not evidence of absence.

The study ended with the conclusion that ‘it is important to maintain a healthy skepticism about the existence of MSG sensitivity in individuals with asthma’. A year later, DD Stevenson published a review about MSG and asthma, seriously criticising the Australian doctors’ study of MSG-induced asthma.

The full story of the relationship between Drs Simon and Stevenson and the glutamate industry is discussed in article, ‘A study in suppression of information’ By Dr Adrienne Samuel, published in the journal Accountability in Research, available at www.truthinlabeling.org/1-manuscript.htm

The verdict

In July 1977, David Livingstone went to court against Marie Callender’s Inc. Dr Simon from the Scripps was called as an expert witness in the courts case. You can read about his testimony at www.truthinlabeling.org/scripps1.

Mr Livingston’s strict liability claim was dismissed on the ground that there was nothing wrong with the soup, or the MSG in the soup. At an application for appeal in March 1999, the matter was remanded for a retrial, on the issue of whether any defendant is liable for ‘failure to warn of an ingredient to which a substantial number of the population are allergic’ and ‘ the ingredient … is one which the consumer would reasonably not expect to find in the product …’. You can read this court report at http://caselaw.findlaw.com.data2/californiatstatecases/b115078.pdf.

How to recognise industry funded research

You can find studies about monosodium glutamate in the Medline medical database at www.pubmed.com. Keep in mind that 13 of the world’s top medication journals imposed rules regarding disclosure of company ties in 2001. Here are some hints from Dr Samuel about how to recognise the influence of industry in research or public talks:

· Researchers will claim MSG is safe.

· They will refer to studies as ‘randomised double-blind cross-over design’ which gives the casual reader the impression that subjects were drawn randomly from the general population – in fact, subjects are often carefully selected.

· Conclusions will not follow from the results in the study.

· Critics of MSG will be disparaged or made the subject of jokes - critics don't report adverse reactions, they ‘complain’.

· Jokey generalisations are presented in serious papers – ‘if you eat too much of anything you'll get sick’.

· Existing data may be distorted or trivialised.

· Reports of human suffering are dismissed as anecdotes.

· Inaccurate generalisations will be presented by alleged authorities - ‘monosodium glutamate has been used in the Orient for more than 2,000 years’ (it was only synthesised in 1902)

What we know

· some consumers are affected by MSG

· reactions can vary (for example, migraine, asthma, irritable bowel symptoms, difficulty sleeping, heart palpitations, pseudo heart attack, heart arrhythmia, numbness, irritability, restlessness)

· some people are more sensitive than others

· effects are related to dose

· children are more vulnerable to the effects of additives than adults.

How necessary is it?

MSG is an unnecessary additive. Our grandparents lived their whole lives without adding it to their foods. Its only benefits are to make stale, cheap or inferior ingredients taste irresistible. The glutamate industry promotes MSG as an appetite enhancer for the elderly but appetite enhancers are the last thing we need during a global epidemic of obesity.

The new MSG

In 1994, Australian food regulators approved a new flavour enhancer called Ribonucleotides (flavour enhancer 635), a combination of disodium guanylate 627 and disodium inosinate 631. Researchers had recently discovered that combining some of these additives with MSG could enhancer the effects of MSG up to 10-15 times. Furthermore, if natural forms of MSG such as yeast extract or hydrolysed vegetable protein were used with ribonucleotides, the label could claim NO ADDED MSG. As products containing the new MSG started to appear on supermarket shelves, the Food Intolerance Network started to receive reports of reactions. As well as the usual set of food intolerance reactions, flavour enhancer 635 seems to be particularly associated with dramatic itchy skin rashes and sometimes swelling of the lips and tongue in children and adults who had never suffered from skin complaints. Because the reactions are often delayed by hours or even days, most consumers never realize the cause of their rash and some can suffer for years. Incredibly, it seems this new additive was never assessed for safety before approval, and our food regulators refuse to accept ‘anecdotes’ about its effects. See separate RiboRash Factsheet.

How to avoid MSG and other flavour enhancers

Don’t expect to find ‘MSG’ on the label

MSG or glutamates can appear in foods under a number of descriptions, see box. MSG is considered to be natural, so the ‘3 No’s’ or any other advertising about ‘all natural, preservative-free, no artificial colours or flavours’.

Flavour enhancers can appear in foods under the following description

Glutamic acid (620)

Monosodium glutamate (621)

Monopotassium glutamate (622)

Calcium glutamate (623)

Monammonium glutamate (624)

Magnesium glutamate (625)

Hydrolysed vegetable protein (HVP), other forms of hydrolysed or autolysed protein

Hydrolysed plant protein (HPP)

Natural flavourings

Flavours

Kombu extract

Yeast extract

Accent

Ajinomoto

Zest

Gourmet powder

Chinese seasoning

Ve-tsin powder

The new MSG: Flavour enhancers 627, 631, 635

Disodium guanylate 627

Disodium inosinate 631

Disodium 5’ribonucleotides 635, also called ribonucleotides or nucleotides

Nucleotides are possibly added to unbaked products such as chicken nuggets in ‘bakers yeast’

Look for some form of MSG and/or other flavour enhancers in foods such as the following

Flavoured chips and snacks • flavoured noodles and snacks with flavour packs or sachets• savoury biscuits and crackers with flavours such as pizza or chicken and even ‘plain’ rice crackers • soups or sauces (canned, packet, restaurant) • stock cubes, stocks • gravy mix • crumbing mixes • seasoned salt • prepared meals • slimmers, lite or ‘healthy’ products and meals • frozen foods and meals • pies, party pies and sausage rolls • fresh sausages, marinated meats and stuffed or seasoned chicken • bottled soy or oriental sauces (note that naturally brewed soy sauce is a form of natural MSG) • deli, manufactured meats or mechanically reclaimed meat such as devon, some hams, luncheon chicken and turkey, chicken nuggets • flavoured tuna • vegetarian burgers and sausages

Supermarket foods likely to be free of MSG

Breakfast cereals

Rice, oats, flour, pasta

Fresh meat, fish and plain chicken

Eggs

Most fresh, canned or frozen fruit and vegetables

Dried beans and lentils

Sweet biscuits or cookies

Sweets (candies)

Dairy products including icecream

Fast food

Expect that most takeaways and food from fast food restaurants will contain some form of flavour enhancers, especially in meat and chicken or vegetarian meat substitutes. Your best bet is unbattered, uncrumbed, grilled fish, or baked potato carts.

Other restaurants

Many restaurants use MSG, even if they have a sign saying they don't. You can ask. Sometimes they will say ‘only a little bit’. Staff in large chains and cafeterias probably won't know. Sometimes staff genuinely don't know, for example when HVP or soy sauce and fish sauces are used for flavouring.

The best way to eat out is to find a small restaurant with a friendly, helpful staff. Ask them whether food is prepared on the premises. Choose simple dishes made from fresh, natural ingredients. Avoid prepackaged foods and crumbing (eg prawn cutlets) or seasoning mixes (eg veal parmigiana). Be very suspicious of any soups, sauces, gravies or dressings. Identify a few safe dishes, and stick to them.

Other food chemicals can cause problems too

MSG and nucleotide flavour enhancers are not the only food chemicals that can cause a wide range of side effects including asthma, skin rashes, headaches, sleeping and behavioural disturbances. For more information, see www.fedup.com.au

References

Allen D, Delohery J and Baker G, Monosodium L-glutamate-induced asthma J allergy Clin Immunol 1987 80(4) 530-53.7

Blaylock R, Excitotoxins: the taste that kills, Health Press, New Mexico, 1995.

Gann D, Ventricular tachycardia in a patient with the "Chinese restaurant syndrome". South Med J 1977;70(7):879-81.

Geha RS and others, Review of alleged reaction to monosodium glutamate and outcome of a multicentre double-blind placebo controlled study Journal of Nutrition 2000 130:1058S-1062S as described in Samuel’s article.

Kerr GR and others, Prevalence of the "Chinese restaurant syndrome". J Am Diet Assoc 1979 75(1):29-33.

Lee EH and Lee DI, A study on intake level of monosodium glutamate in Korea. Korean J Environ Health Soc 1986 12:75-85.

Moneret-Vautrin DA, Monosodium glutamate-induced asthma: study of the potential risk of 30 asthmatics and review of the literature. Allergie et Immunologie 1987; 19(1):29-35.

No MSG website: www.NOMSG.com

Reif-Lehrer L, A questionnaire study of the prevalence of Chinese restaurant syndrome, Fed Proc 1976 35(11):2205-11.

Rhodes J and others, A survey of the monosodium glutamate content of foods and an estimation of the dietary intake of monosodium glutamate. Food Addit Contam 1991 8(5): 663-72 and 8(3):265-74.

Samuel A, The toxicity/safety of processed free glutamic acid (MSG): a study in suppression of information. Accountability of Research. 1999;6(4):259-310. Available in full on the website: www.truthinlabeling.org

Schaumburg HH and others, Monosodium l-Glutamate: its pharmacology and role in Chinese restaurant syndrome. Science, 1969;163:826-828.

Schwartz GR, In bad taste: The MSG Syndrome, 1988, Signet New York.

Sommer R. Yeast extracts: production, properties and components. 9th International Symposium on Yeasts, Sydney 1996.

Stevenson DD, Monosodium glutamate and asthma J Nutr 2000 130:1067S-1073S.

Tsuji S and others, 1996 Estimation of daily intake of chemically synthesised natural food additives from processed foods in Japan. 1996. J Food Hyg Soc. 37:308-317.

Woessner KM, Simon RA and Stevenson DD. Monosodium glutamate sensitivity in asthma. J Allergy Clin Immunol 1999 104 (2-Pt 1): 305-10.

Conflicts of interest in medical journals – ‘Lies, damn lies and statistics’,New Scientist, Editorial page 3, 15 Sept 01 and ‘Trust me, I'm a Scientist’, by Arnold Relman page 46-47, 22 Sept 01

‘Scientists Call on Journals to Disclose Authors’ Conflicts of Interest’, CSPI Media release 4 Feb 2002, www.cspinet.org

- Adapted from Fed Up with Asthma by Sue Dengate, Random House, Sydney, 2003.

www.fedup.com.au

The information given is not intended as medical advice. Always consult with your doctor for underlying illness. Before beginning dietary investigation, consult a dietician with an interest in food intolerance.

Update July 2006