Introduction: From a Traditional Chinese Medicine perspective, autumn is the season for nourishing the lungs. White-colored foods are believed to benefit the lungs, so it is advisable to consume more pears, white peaches, and their juices. Seasonally, autumn fruits include apples, pears, and oranges, which are recommended choices.
I. What constitutes juice?
The "juices" on store shelves are often misleading. Only 100% fruit juice can be legally called "juice." Others are "fruit juice drinks," which are made by adding large amounts of water, sugar, acidity regulators, colors, and flavors to juice. In contrast, fruit juice is made from fruit through physical processes like crushing and pulping, or by reconstituting concentrated juice with an equivalent amount of water. It may use sugar, acidulants, or salt, but not both sugar and an acidulant simultaneously. Therefore, fruit juice has a higher fruit content and fewer, if any, additives compared to fruit juice drinks.
II. How does the nutrition in juice compare to whole fruit?
Whether fresh-squeezed or industrially produced 100% pure juice, it will have a loss of vitamins, especially heat-sensitive ones, and antioxidant components compared to fresh fruit. Dietary fiber is also lost.
1. Vitamin Loss. Taking Vitamin C as an example, it reacts when it encounters Vitamin C oxidase and oxygen. In a whole fruit, the enzyme and Vitamin C are in different locations within cells and tissues, so they don't meet, and there is no oxygen present. However, the crushing and pulping processes in juice production bring these three elements together, creating the conditions for the reaction. Thus, vitamins are lost in juice compared to whole fruit. The loss of antioxidant components follows the same principle.
2. Loss of Dietary Fiber. The process of making fruit juice removes some dietary fiber, with varying degrees of loss depending on the type. For example, apple juice is a clarified juice, and its production removes most of the dietary fiber. In contrast, orange juice retains more of its fiber.
This doesn't mean juice is without merit. Compared to fruit, it can be richer in various minerals; drinking 100ml of juice will certainly provide more minerals than eating 100g of fruit. Although some dietary fiber is lost, it still provides a portion. Additionally, juice is convenient to drink (no washing required) and to carry. Furthermore, processes like high-temperature pasteurization and aseptic packaging give it a longer shelf life.
III. What are the benefits of these five fruit juices (pear, apple, peach, orange, grape) and tomato juice (a vegetable juice) for the human body?
These five juices can supplement the body with various minerals, with their mineral content being quite similar. They contain various organic acids that can stimulate the appetite. Among them, pear, peach, and orange juices are cloudy juices, which are relatively rich in dietary fiber and can be part of the daily diet.
Pear juice is known for its effects of moistening the lungs, clearing dryness, and resolving phlegm to relieve coughs.
Research indicates that the flavonoids and polyphenols in apple juice have anti-cancer properties. A study by the American Academy of Pediatrics suggests that for children, 100% juice (especially apple juice) is the best beverage after milk, dairy products, and water.
Orange juice is rich in beta-carotene, which the body can convert into Vitamin A. It is recommended for individuals who frequently use computers to supplement their intake. It also plays a positive role in maintaining immunity and the integrity of skin and mucous membranes.
Grape juice contains anthocyanins, which have antioxidant effects, help prevent cardiovascular and cerebrovascular diseases, and lower blood pressure.
Tomato juice, a vegetable juice, has the nutritional advantage of being low in sugar and thus lower in energy compared to fruit juices. It contains lycopene, an antioxidant whose potency is 3.2 times that of beta-carotene and 100 times that of Vitamin E. Additionally, lycopene can reduce the risk of atherosclerosis and coronary heart disease. For those who don't like sweet juices, tomato juice is a good alternative.
IV. What fruits and juices should be supplemented most in the fall? Are there any special considerations for certain populations, such as those with high blood sugar?
From a Traditional Chinese Medicine perspective, autumn is the season for nourishing the lungs. White-colored foods are believed to benefit the lungs, so it is advisable to consume more pears, white peaches, and their juices. Seasonally, autumn fruits include apples, pears, and oranges, which are recommended choices. However, since different fruits have unique nutritional profiles, it's best to eat a variety to ensure a balanced nutrient intake.
For special populations, there are specific considerations when consuming juice. For individuals with high blood sugar, those managing their weight, and those with excessive stomach acid secretion, there are different points to consider.
For people with high blood sugar, the first principle of diet is to control total energy intake, and the second is to eat smaller, more frequent meals. Juice is high in sugar, and drinking too much will add extra calories. Therefore, if consumed, the amount must be controlled. It is also recommended to choose juices made from low-GI (Glycemic Index) fruits, such as peaches or pears.
For individuals trying to control their weight, if they don't like eating whole fruits and vegetables but are willing to drink juice, they can switch to vegetable juice. Vegetable juice has a lower sugar content, such as tomato juice.
For those with excessive stomach acid secretion, it is advisable to limit juice consumption to avoid the acids in the juice stimulating further acid secretion.
V. How should juice be consumed? This includes: when is the best time to drink it? What is the most nutritious way to pair it? What is the appropriate daily amount of fruit, and what is the equivalent in juice? Are there any禁忌 (taboos) for drinking juice?
Because juice is high in sugar, drinking it with meals as a substitute for water will increase calorie intake. It is recommended to drink it between meals, for example, at 10 AM or 3 PM. At these times, energy from the previous meal is mostly depleted, and juice can quickly replenish energy and provide various minerals. Along with the juice, a small handful of nuts can be consumed, but the portion should be controlled (about one handful in the shell).
The Chinese Dietary Guidelines recommend consuming 200-400 grams of fruit per day. The juice yield varies by fruit: generally, orange juice has a yield of 47-48%, apple juice 80%, and peach and pear juices 70-80%. Therefore, 400 grams of oranges is equivalent to 200ml of orange juice; 400 grams of apples is equivalent to 320ml of apple juice; and 400 grams of peaches or pears is equivalent to 280-320ml of peach or pear juice, respectively.
The first principle of drinking juice is to control the portion size to obtain the nutritional benefits of juice while avoiding excessive calorie intake. When whole fruit intake is insufficient, some juice can be used to supplement nutrients from different fruits. (Guo Chuanling, Master of Nutrition and Food Hygiene.)