In recent times, there has been a growing trend on social networks promoting the consumption of vegetable juice for beauty and health benefits. The belief is that vegetables are packed with essential vitamins and minerals while having lower sugar content compared to fruit juice.
Many people assume that freshly squeezed vegetable juice retains the maximum amount of nutrients since cooking methods often lead to the loss of water-soluble and heat-sensitive bioactive compounds. Furthermore, the vibrant green color of vegetable juice gives it a perceived sense of healthiness.
It is important to note that drinking vegetable juice may not necessarily lead to detoxification and can even pose some health issues. When using a juicer or commercially available vegetable juice, some dietary fiber found in vegetables is lost as the vegetable residue gets filtered out.
Commercially available vegetable juice typically contains only about 1% dietary fiber, half of what is present in fresh fruits and vegetables, which leads to a significant loss.
The process of juicing vegetables also results in a considerable loss of vitamins, particularly vitamin C (VC), due to oxidation. Heating during conventional cooking also contributes to vitamin loss.
It is worth noting that cooking is necessary for certain dishes, and heating doesn't only lead to nutrient loss but also the loss of lectins, tannins, cucurbitacins, oxalic acid, and other substances. While these compounds act as protective "umbrellas" for plants against microorganisms and insects, they can become "toxins" for humans.
Tannins, commonly found in persimmons, unripe grapes, and plums, can combine with proteins to form tannates. In the presence of excessive stomach acid, they can mix with pectin and fiber, forming hard lumps that may cause digestive tract obstruction, severe abdominal pain, vomiting, and other symptoms.
Certain legumes and tubers, such as beans, fava beans, and potatoes, contain toxic proteins known as agglutinins that cause the agglutination of red blood cells.
Additionally, oxalic acid can combine with calcium ions in the body to form calcium oxalate, leading to the formation of kidney stones and the deposition of sharp crystals in various tissues and organs. Vegetables with high oxalic acid content include spinach, sweet potato, celery, and broccoli.
For those interested in drinking vegetable juice, there are ways to minimize safety risks and take additional precautions:
1. Utilize a wall-breaker: Wall-breakers, a popular tool nowadays, can crush vegetable scraps into suitable particle sizes, helping retain dietary fiber while maintaining an acceptable taste.
2. Blanch before juicing: Blanching vegetables not only reduces oxalic acid content but also removes surface microorganisms and certain pesticide residues, significantly improving safety. A brief blanching after juicing can also minimize vitamin loss caused by oxidation.
3. Opt for fruit flavoring: Instead of adding sugars like honey or sugar, it is healthier to incorporate fresh fruits and vegetables as natural sweeteners. To address concerns about sugar intake, simply subtract the number of fruits added to the vegetable juice from daily fruit consumption.
4. Moderate consumption: Vegetable juice should not replace the complete consumption of vegetables during three meals. It should be considered as a supplementary option when daily vegetable intake is insufficient. Emphasis should still be placed on consuming whole vegetables and fruits regularly.
