excessive sodium (eg. salt or other sodium containing additives such as monosodium glutamate (MSG) ) may cause
hypernatraemia as well as
hypertension
the global average sodium intake for adults is estimated to be 4,310 milligrams per day (equivalent to 10.8 grams per day equivalent of table salt), which is more than double the WHO recommendation of less than 2,000 mg each day of sodium (or less than 5g per day salt)
simple sugars
purines
these are completely metabolized by xanthine oxidase in the gut or in the liver to harmful uric acid and high levels may result in
gout in susceptible people
very high purine foods include:
offal (liver, kidneys, sweetbreads, heart, and brains)
certain seafoods - anchovies, sardines, herring, mackerel, mussels, scallops, and gamey fish like trout
game meats - venison, pheasant, wild boar, and rabbit
yeast extracts and yeast-based drinks - Vegemite (23-90mg per 5g serve), Marmite, and brewer's yeast (500ml beer: lager 20-50mg, ale 30-90mg, stout/craft 75-140mg)
high purine foods include:
other meats and seafood eg. 300g steak = 330-400mg purines; 150g roast chicken= 165-210g; 150g barramundi = 135-165mg; 150g salmon = 150-195mg; for gout patients 100g serves of salmon or barramundi are recommended once or twice a week - minimise red meats and poultry;
certain vegetables - asparagus, spinach, mushrooms, green peas, and cauliflower
legumes - lentils, chickpeas, beans, and soybeans
NB. plant based purines excluding yeast are generally low in the troublesome hypoxanthine and the dietary fiber and slowed digestion with microbial action results in a much lower and slower absorption of uric acid and very little absorption of hypoxanthine (which otherwise will be converted to uric acid by xanthine oxidase in the liver) hence these are unlikely to cause gout
ultra-processed foods
these often have high levels of salt, nitrates, and a range of other food additives
the following additives reflective of ultra-processing of foods were found to be linked to higher mortality in a 2025 study
13):
glutamate and ribonucleotides (flavor enhancers); acesulfame, saccharin, and sucralose (sweeteners); caking agents, firming agents, thickeners (processing aids); and fructose, inverted sugar, lactose, and maltodextrin (sugars).
a 2026 study showed that 71% of grocery store baby food products in the US are classified as ultra-processed foods (UPFs)
14) high levels of these foods are linked with a range of conditions including:
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fruit juice
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excessive intake of fructose (eg. high fructose corn syrup, fruit drinks, etc) may cause:
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fructose metabolism in the liver rapidly consumes ATP, accelerating internal purine breakdown and spiking uric acid levels
fructose causes hyperuricemia as its hepatic metabolism through the aldolase reductase pathway produces uric acid
glucose-fructose mix in sugary drinks
appears to fuel metastasis speed of
colorectal cancer (bowel cancer) to the liver by activating an sorbitol dehydrogenase (SORD), which boosts glucose metabolism and triggers the cholesterol pathway, ultimately driving metastasis
19) appears to give a 2-3x risk of
stomach cancer just having one carbonated sugary drink per day
20)
fat soluble vitamins such as:
vitamin A - eating excessive amounts of liver, egg yolk, etc
vitamin D - eating excessive amounts of fatty fish like salmon, herring, and mackerel, and egg yolks
pyridoxine (vitamin B6) supplementation of foods and drinks (especially if also take pyridoxine tablets) may result in toxicity causing peripheral neuropathy
flourine - flouridation of water supplies may lead to dental flourosis (cosmetic mottling of teeth) and if very high levels from other sources, skeletal flourosis and possible other effects but these are rare
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can bind to and agglutinate red blood cells is well known and used for blood typing
can bind avidly to mucosal cells and interfere with nutrient absorption from the intestine
lectins isolated from black beans can produce growth retardation when fed to rats at 0.5% of the diet, and lectin from kidney beans causes death within two weeks when fed to rats at 0.5% of the diet.
Soybean lectin produces growth retardation when fed to rats at 1% of the diet.
castor bean lectin ricin (one of the most toxic natural substances known) is notorious for causing deaths of children, and has been used as an instrument of bioterrorism
Phytohaemagglutinin (PHA) is a lectin found in significant quantities (as much as 2.4–5% of total protein) in legumes such as red or white kidney beans, green beans and fava beans. PHA has a number of different properties, including the ability to induce mitosis, affect membrane transport and permeability to proteins, and agglutinate red blood cells.
legumes should generally be cooked to reduce amount of PHA
excessive iodine intake
impairs immune function and may promote oxidative stress, altered cytokine profiles, and autoimmune thyroiditis in genetically and epigenetically susceptible individuals
21)
goitrogens (glucosinolates) in Brassica spp.
these interfere with the thyroid uptake of iodine causing goitres and
hypothyroidism most are inactivated by cooking
spinach, cassava, peanuts, soybeans, strawberries, sweet potatoes, peaches, pears, and vegetables in the Brassica genus
consumption of large quantities of uncooked kale or cabbage
erucic acid in rape
furocoumarins may cause photosensitivity as well as inhibiting liver enzymes (eg. bergamot in citrus peel, poorly stored parsnips)
amylase inhibitors
anti-thiamine compounds
Thiaminase (destroyed by cooking) is found in fish, crab, clams and in some fruits and vegetables such as blueberries, black currants, red beets, Brussels sprouts and red cabbage
pyrrolizidine alkaloids (PAs)
found in comfrey, etc
Serious incidences of illness have been reported in people consuming cereal grains that are contaminated with the seeds of PA-containing plants
PAs are also present in milk from cows and goats and in honey
oxalates
zucchini and cucurbitacins
shiitake mushrooms (when eaten raw or only lightly cooked)
2% of people may develop shiitake flagellate dermatitis which occurs 12hrs to 5 days later and lasts 3weeks
appears to be a reaction to lentinan, a thermolabile polysaccharide
coumarins (tonka bean, woodruff, clover)
phytates and phytic acid
hypoglycin in ackee
safrole
myristicin
tomatine in unripe tomatoes
Japanese star anise
turmeric in high doses as with supplements may cause severe hepatotoxicity which may be lethal - max daily intake should be 1.5-3g (half to one teaspoon)
“unwashed” / “raw” poppy seeds in large amounts (especially as tea) may cause opiate effects and dependence as well as potential for overdose
large amounts of “raw” poppy seeds from certain batches with high than usual levels of thebaine drank as home brewed poppy seed tea resulted in 19 people being hospitalised in Australia in 2022 including 1 cardiac death and 2 in ICU due to the chemical thebaine (this is normally destroyed when the seeds are cooked) which can cause seizures, severe muscle pain and severe muscle spasm, cramping, stiffness or abnormal movements and acute kidney injury
when large quantities of poppy seeds are brewed under certain conditions, the drink can offer a narcotic, possibly hallucinogenic, high.
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some artificial sweeteners
erythritol
may build up as is only excreted in urine and those with high levels appear to have twice the cardiovascular risks
22) appears to increase stroke and AMI risks by having endothelial pro-thrombotic and vasoconstrictive effects
23)
many “natural / herbal medicines”
substances formed as the result of product abuse
substances formed as the result of food processing
heterocyclic aromatic amines
polycyclic aromatic hydrocarbons (PAHs)
acrylamide
chloropropanols
furan
trans fatty acids
nitrites, nitrates and nitrosamines formed during drying, curing and preserving eg. processed meats
nitrosamines are carcinogenic
nitrates increase risk of aberrant S-nitrosylation, a chemical process whereby a molecule related to nitric oxide (NO) binds to sulfur (S) atoms within proteins (producing “SNO”)
aberrant S-nitrosylation reactions contribute to some forms of cancer, autism, Alzheimer's disease, Parkinson's disease and other conditions
S-nitrosylation of protein CRTC1, impairs its ability to regulate genes that are critical for forming and maintaining connections between brain cells, an essential process for learning and long-term memory
24)
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nitrates have been used in curing meats for centuries (initially as contaminated with salt and later in the 16thC, intentionally by adding saltpetre which was also a critical ingredient of gunpowder, when it was found that the nitrate was converted to nitrite by bacteria in the meat, in the 1920's nitrite was added instead of nitrate which allowed more precise and lower amounts to be added with confidence) as they solve several problems:
nitrite prevents Clostridium botulinum spores from germinating and producing botulinum toxin
nitrite via nitric oxide binds myoglobin to keep it pink instead of going grey (discovered by Haldane in 1901)
nitrite reduces the rate the fat goes rancid
Kerner, a German doctor documented over 200 cases of sausage poison between 1817-1822 which he supposed was from a toxin in food - and it was called Kerner's disease or, later botulism (from the Latin for sausage) - the bacterium was found 70 yrs later after another outbreak from ham and the toxin was given its name
in the early 1970's it was discovered that the nitrite when heated with proteins as in cooking bacon, resulted in the production of nitrosamines which were found to be carcinogenic hence in 1978 it was mandated that ascorbate or erythrobate was added to bacon to reduce the formation of nitrosamines
in 1978, a rat study showed being fed nitrites resulted in twice the rate of lymphomas but 2 years later the study was reviewed and found to be erroneous and there was no evidence that lymphoma rates were increased.
in 2015, the WHO International Agency for Research on Cancer concluded that processed meats were Group I carcinogens which indicates confidence in evidence that they can cause cancer but does not ascribe what that risk is which was given as being there is a 18% higher risk of colorectal cancer per 50g per day intake of processed meat
in 2023-2025, Europe lowered the permissible amounts of nitrite to a level which still minimised the risk of botulism and thus bacon is much safer now
just adding salt to meat does nothing to prevent botulism, but it will delay the meat going off from other bacteria
“uncured meat” products with “no added nitrates or nitrites” is actually misleading as they usually add nitrates via adding celery and a starter culture of the right bacteria to convert it to nitrite which is back to the imprecise Medieval method but it is required to be labeled uncured as it does not have synthetic additives but only biologic additives
interestingly, 80% of dietary nitrates come from leafy vegetables, celery and beetroot and the oral microbiome can convert these to nitrites but this needs further research
biogenic amines
titanium dioxide
has been used as a food additive but there are concerns it may increase gut inflammation and damage DNA - particularly nanoparticles of TiO2
although poorly absorbed, in higher doses, it may accumulate in the liver, spleen, and kidneys
European Union banned TiO2 as a food additive in 2022
chemical residues sprayed onto foods, on food containers, or from residual dust
herbicides
glyphosate
if applied too early, higher chemical residues can remain on mung bean seeds during harvest, which risks them exceeding acceptable export levels as occurred in 2026 when China rejected an Australian export of mung beans
25)
pesticides
organophosphates such as dimethoate and omethoate are still sprayed onto berries, mangoes, avocados and citrus fruits in Australia mainly to control spread of the Queensland fruit fly which has spread to now be from Darwin across to the east coast and down to Melbourne and NW Victoria but WA and Tas are free of it although WA has the Mediterranean fruit fly
dimethoate was banned by the European Union in 2019 and has been classified by the United States Environmental Protection Agency as a “possible human carcinogen”
26) its use was banned on stone fruit, grapes, figs, guavas and strawberries in Australia in 2011
its use as a post-harvest dip to control fruit fly on avocados, mangoes and other tropical fruits like bananas, custard apples, feijoas, guavas, lychees and pawpaw “may not meet the safety criteria” and hence its use was suspended in Australia on these fruits in 2023
27) use on inedible peels makes it very low risk for humans in either ingestion quantities (unless you eat the peel) or skin absorption but the ongoing use on blueberries and raspberries is a potential issue if not thoroughly washed and these form a significant part of the diet
ingested doses of 1mg/kg/d in humans do not cause symptoms but do reduce blood cholinesterase activity hence human consumer risks are regarded as low.
dimethoate was banned in Europe in 2019 and it has been classified it as a “possible human carcinogen”.
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exposures generally occur from drinks (plastic water bottles or processed drinks, or contaminated water supplies) or from contaminated foods
water supplies may be contaminated particularly after these chemicals are used to put out major fires and the rain run off takes it into reservoirs
in 2025, various city drinking water supplies have been found to be contaminated eg. in Sydney, 31 PFAS chemicals were found in drinking water from sites at Ryde, Potts Hill, Prospect and North Richmond although they are currently at low “safe” levels
levels in 2 yr old children are particularly high - mainly from ingestion via contaminated fingers or foods
28) choose safer products: Look for “phthalate-free,” “paraben-free,” and “fragrance-free” labels
avoid plastics labeled #3, #6, and #7 as these may contain BPA or similar chemicals, and avoid using plastics in microwaves to heat food
wash hands frequently, especially before eating
ventilate your home and use HEPA filters, when possible.
limit pesticide exposure: Wash produce thoroughly and consider organic options
clean regularly: use a damp cloth to reduce dust that may contain chemical residues
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contamination of food growing cycles