Essential Elements
The living organisms are made of 20 essential elements. Carbon, hydrogen, oxygen and nitrogen (C, H, O and N) are the 4 main elements that account for about 96% of our total weight.
Oxygen is the most abundant element in human body, because various organic compounds contain them and two-thirds of our body is water (H₂O). In different organisms, element types are roughly the same, but their content varies greatly.
Four electrons need to be acquired by carbon to create a stable structure. Other atoms share electron pairs with them to form covalent bonds. They also bond with each other to make large chains or rings. Sugars, fats, proteins, and nucleic acids are four major biological macromolecules that are based on carbon skeletons. Therefore, carbon is the second most abundant element in living organisms, and life on Earth is built on them.
The content of major elements or macroelement is greater than 0.01% (C, H, O, N, P, S, K, Ca, Mg); trace elements is less than this figure (Fe, Mn, Zn, Cu, B, Mo, Cl, etc).
Non-essential Elements
The absence doesn’t significantly impact us. Its physiological functions have not been fully clarified. These elements may be present in the human body, but they are not essential for sustaining life. Minor hazards often make their toxicity overlooked. The most classic example is organic germanium dietary supplements in the late 20th century. It started trending in Japan in 1970s and later became popular in other countries. Germanium organic compounds were once considered a panacea for curing diseases and promoting health. However, doctors found that long-term use of these compounds had strong toxic side effects. Many patients suffer from ailments such as kidney dysfunction. Recovery of renal function is slow and incomplete even long after germanium intake was stopped. Other symptom include anemia, muscle weakness, and peripheral neuropathy. Currently, there are no documented symptoms of germanium deficiency.
Researchers studying biological effects in areas abundant in rare earth mineral found that children's IQ, memory, and reasoning scores in those regions were significantly lower. The investigation also found a significant decrease in the speed of central nervous system bioelectric conduction in adults. Animal experiments showed that certain doses of rare earth minerals could lead to a decline in learning and memory abilities, significant changes in the levels of trace elements and a marked reduction of enzyme activity in the brain hippocampal tissue. Ultimately, it damages rats brain function significantly. Clearly, we should adopt a cautious attitude towards the development and use of non-essential elements, especially in food and health products.
| Non-Essential Element | Common Sources | Possible Effects and Remarks |
|---|---|---|
| Titanium (Ti) | Food additives, cosmetics, dental implants | Generally non-toxic, widely used in medical and pigments and additives. |
| Aluminum (Al) | Beverage cans, cookware | Generally non-toxic, but long-term high-dose intake may be associated with neurodegenerative diseases. |
| Silicon (Si) | Plant-based foods (such as grains, vegetables), drinking water | May contribute to bone and connective tissue health, specific mechanisms not well understood. |
| Barium (Ba) | Certain foods, drinking water | Used as a contrast agent in medical imaging, low-level intake generally harmless. |
| Arsenic (As) | Certain groundwater, pesticides, wood preservatives | Small doses can act as medicine, but long-term low-dose exposure lead to skin damage, neurological issues, and cancer. |
Harmful Elements
They have a clear negative impact on human health. Even small amounts can result in serious health damage. Mercury and lead are two well-known harmful elements that have become major public health issues due to their widespread use and significant toxicity.
Mercury is a heavy metal that exists in various forms. Methylmercury is extremely dangerous in environment because it accumulates through the food chain, particularly in aquatic ecosystems. Humans primarily ingest it through the mercury-contaminated fish and seafood. The symptom of its toxicity manifests as the weakened nervous system. Infants and children are especially sensitive, and exposure to mercury will cause intellectual development disorders and problems with memory and attention. In adult，the impaired motor coordination, vision, hearing and language ability are often relative to mercury poisoning.
Lead is another heavy metal extremely harmful to human health. Although it isn’t used in today's new product, such as unleaded gasoline and lead-free formulations in paints, the old pipes and paints are still common sources of lead exposure. Like mercury, lead also damages our nervous system. The deafness of famous musician Beethoven was attributed to drinking vessels containing lead.