330 mL 可乐：~35 g 糖，~140 kcal330 mL 橙汁（100% 鲜榨）：~30 g 糖，~150 kcal500 mL 运动饮料（如佳得乐）：~30 g 糖，~130 kcal500 mL 瓶装调味茶：~20-35 g 糖，~80-140 kcal500 mL 奶茶（全糖）：~50-70 g 糖，~300-500 kcal250 mL 苹果汁（工业）：~26 g 糖，~115 kcal 世卫组织（WHO）关于糖摄入的指南建议，游离糖不超过每天总热量的 10%（强推荐），最好再降到 5% 以下（有条件的建议）。对一个普通成年人，这大约是每天 50 g 和 25 g。WHO 把果汁里的糖也算作游离糖；整颗水果、蔬菜和奶里本来就有的糖不算。一杯全糖奶茶就能让你超出 25 g 那条线两三倍。
果糖和葡萄糖的代谢路径不同。葡萄糖进入血液后被全身细胞利用，路上有一道严格的限速关卡（磷酸果糖激酶，PFK）管着用量。果糖不一样：它在小肠和肝脏被迅速摄取，绕过那道关卡直接往下走。大量摄入时，肝脏会把果糖里多余的碳变成脂肪，重新组装成，装进 VLDL（肝脏往外运脂肪的颗粒）送进血液。这个过程叫脂肪新生（de novo lipogenesis, DNL）。
Imamura, F., O'Connor, L., Ye, Z., Mursu, J., Hayashino, Y., Bhupathiraju, S. N., & Forouhi, N. G. (2015). Consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice and incidence of type 2 diabetes: systematic review, meta-analysis, and estimation of population attributable fraction. BMJ, 351, h3576. 17 cohorts (38,253 cases; 10,126,754 person-years). Per serving a day: sugar-sweetened beverages +18% (+13% after adjusting for adiposity); artificially sweetened beverages +25% (+8%), with publication bias and residual confounding indicated; fruit juice +5% (non-significant) and +7% after adjustment. Population attributable fraction for SSB: 8.7% in the US, 3.6% in the UK (abstract, PMID 26199070). 10.1136/bmj.h3576
World Health Organization. (2015). Guideline: Sugars intake for adults and children. Geneva: WHO. Recommends reducing free sugars to <10% of total energy intake (strong recommendation), and suggests a further reduction to <5% (conditional). 'Free sugars' include monosaccharides and disaccharides added by the manufacturer, cook, or consumer, plus sugars naturally present in honey, syrups, fruit juices, and fruit juice concentrates — explicitly distinguishing them from the intrinsic sugars in whole fruit, vegetables, and milk. www.who.int/publications/i/item/9789241549028
Hall, K. D., Ayuketah, A., Brychta, R., Cai, H., Cassimatis, T., Chen, K. Y., et al. (2019). Ultra-processed diets cause excess calorie intake and weight gain: an inpatient randomized controlled trial of ad libitum food intake. Cell Metabolism, 30(1), 67-77.e3. 20 inpatients, 2 weeks per diet, crossover. Meal eating rate was greater on the ultra-processed diet by 17 +/- 1 kcal/min (7.4 +/- 0.9 g/min), p < 0.0001 - that is the between-diet difference; ratings of pleasantness and familiarity did not differ (full text, PMC7946062). Diets were matched for presented calories, energy density including beverages (1.024 vs 1.028 kcal/g), macronutrients, sugar, sodium and fiber (21.3 vs 20.7 g/1000 kcal, partly via fiber supplements added to ultra-processed meals); non-beverage energy density was 1.957 vs 1.057 kcal/g (~85% higher), which the authors say likely contributed. Intake was 508 +/- 106 kcal/day greater on the ultra-processed diet (full text, Table 1 and Results). 10.1016/j.cmet.2019.05.008
DiMeglio, D. P., & Mattes, R. D. (2000). Liquid versus solid carbohydrate: effects on food intake and body weight. International Journal of Obesity, 24(6), 794-800. Crossover in 15 adults (7 men, 8 women): a daily 1880 kJ carbohydrate load as soda or as jelly beans for 4 weeks each, separated by a 4-week washout. With jelly beans, free-feeding intake fell (dietary compensation 118%); with soda it did not (compensation -17%), so total intake rose by about the size of the load, and body weight and BMI rose only in the soda period. The abstract does not say the order was randomised (abstract, PMID 10878689). 10.1038/sj.ijo.0801229
Stanhope, K. L., Schwarz, J. M., Keim, N. L., Griffen, S. C., Bremer, A. A., Graham, J. L., et al. (2009). Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans. Journal of Clinical Investigation, 119(5), 1322-1334. Overweight/obese adults aged 40-72 drank glucose- or fructose-sweetened beverages supplying 25% of energy requirements for 10 weeks (39 enrolled, 7 did not complete). Weight gain was similar in both groups; visceral adipose volume rose only with fructose. Fructose raised hepatic de novo lipogenesis, 23-h postprandial triglycerides, fasting apoB, LDL, small dense and oxidized LDL, fasting glucose and insulin, and lowered insulin sensitivity; fasting triglycerides rose about 10% with GLUCOSE, not fructose. Neither the abstract nor the full text reports uric acid or urate (abstract, PMID 19381015; full text, jci.org). 10.1172/JCI37385
Lustig, R. H., Schmidt, L. A., & Brindis, C. D. (2012). The toxic truth about sugar. Nature, 482(7383), 27-29. 10.1038/482027a
Muraki, I., Imamura, F., Manson, J. E., Hu, F. B., Willett, W. C., van Dam, R. M., & Sun, Q. (2013). Fruit consumption and risk of type 2 diabetes: results from three prospective longitudinal cohort studies. BMJ, 347, f5001. Across 187,382 participants in three cohorts, higher whole-fruit intake was associated with lower type 2 diabetes risk while higher fruit-juice intake was associated with higher risk; substituting whole fruit for juice was associated with lower risk. Abstract figures (NHS, NHS II, HPFS; 12,198 cases): per 3 servings a week, whole fruit HR 0.98; blueberries 0.74, grapes and raisins 0.88, apples and pears 0.93, bananas 0.95, cantaloupe 1.10; fruit juice 1.08 (1.05-1.11). Observational (abstract, PMID 23990623). 10.1136/bmj.f5001