Detrimental eating habits

In specific individuals, ingesting foods containing natural allergens (e.g. peanuts, shellfood) or drug-induced triggers (e.g. tyramine for a person taking an MAO inhibitor) may be life-threatening.
Some foods have low nutritional value, and if consumed on a regular basis will contribute to the decline of human health. This has been demonstrated by various epidemiological studies that have determined that foods such as processed and fast foods are linked to diabetes and various heart problems.
When improperly cut or prepared, a small number of foods (such as fugu) can result in death.
The ingredient usually cited as being most crucial to good health, water, has even been known to result in death when consumed in extraordinary quantities.