在2026年，“纤维最大化”从披萨面团到软饮料等产品迅速扩散，但最有力的证据仍然集中在全食物中的天然纤维。观察性研究持续显示剂量-反应模式：随着摄入量上升，在约25-30克/天之前，癌症、糖尿病和心脏病风险下降，而高于该范围的额外收益仍不确定。

常见食物中的数字说明为何总量可能误导：两片面包约提供2.5克纤维，约等于一份西兰花或菠菜，而半条全麦面包就能接近日目标。但这在营养上并不平衡，因为与混合水果和蔬菜相比，面包通常提供更少的维生素、矿物质、抗氧化剂和可溶性纤维。

2023年世卫组织的一项综述发现，水果和蔬菜的益处在达到800克/天前持续增加，之后趋于平台，而官方指南仍约为400克/天（五份），这是一个更实用的阈值，仍可帮助多数人达到约30克纤维并获得更好的营养多样性。对于长期低于10克/天的人，营养师建议每隔几天只增加3-5克并保持充足饮水；与天然来源相比，关于提取或合成添加纤维长期结局的证据仍有限。

In 2026, “fibremaxxing” is spreading across products from pizza dough to soft drinks, but the strongest evidence still centers on natural fibre in whole foods. Observational studies consistently show a dose-response pattern: as intake rises, risks of cancer, diabetes, and heart disease fall up to about 25-30g/day, with uncertain additional gains above that range.

Numbers in common foods show why totals can mislead: two slices of bread provide about 2.5g of fibre, roughly matching a serving of broccoli or spinach, and half a loaf of wholemeal bread can approach the daily target. Yet this is nutritionally imbalanced, because bread generally supplies fewer vitamins, minerals, antioxidants, and less soluble fibre than mixed fruits and vegetables.

A 2023 WHO review found fruit-and-vegetable benefits increase up to 800g/day before leveling off, while official guidance remains about 400g/day (five portions), a practical threshold that can still help most people reach ~30g fibre with better nutrient diversity. For people long below 10g/day, dietitians advise adding only 3-5g every few days and maintaining high water intake; evidence for long-term outcomes of extracted or synthetic added fibres remains limited compared with natural sources.

Source: Should you be fibremaxxing?

Subtitle: What to make of the new dietary fad

Dateline: 2月 26, 2026 04:27 上午