中大食品及營養科學教授：大部分人都不知道的健康陷阱 168斷食、生酮飲食到底好不好？NMN、益生菌到底有沒有用？- 張志強教授

Key wellness traps & what to watch for

• Ultra-processed foods are a major risk factor: most packaged “convenience” foods go through extensive processing.
• Check ingredient lists—especially added “Tang/Fat/Salt” (sugar/fat/sodium):
  • If sugar/fat/salt appear high or listed early, treat it as a warning.
• Sugary drinks and fast-absorbing sugars spike blood sugar quickly, increasing risk over time (e.g., insulin resistance → type 2 diabetes).
• High-fructose (fruit syrup / high-fructose corn syrup, HFCS) is specifically concerning:
  • Fructose metabolism heavily involves the liver → can contribute to non-alcoholic fatty liver.
  • Fatty liver is linked with chronic inflammation and downstream risks (e.g., metabolic and heart-related issues).

Self-care & dietary strategies (practical takeaways)

• Reduce or avoid processed foods
  • Prefer unprocessed/minimally processed foods, especially plant-based foods.
• Choose lower glycemic carbohydrates
  • Aim for carbs that digest/absorb more slowly (lower glycemic index).
• Manage sugar intake by prioritizing whole foods
  • Prefer eating whole fruit over drinking fruit juice (juice removes fiber and concentrates sugar).
  • When possible, choose whole fruit portions instead of juice.
• Use “color variety” for plant foods
  • Eat different colors of fruits/vegetables to obtain diverse antioxidants/phytonutrients.
• Fasting window (168 fasting) framed as a scheduling tool
  • The strategy works mainly by creating a consistent eating rhythm and giving digestion/body systems a preparation period.
  • Key caution: within the eating window, choose what/how much you eat well to avoid metabolic problems.
  • Breakfast skipping is personalized—some may benefit, but habits vary.
• Smart breakfast swaps (based on the discussion)
  • If choosing bread: consider whole-grain options rather than highly processed white bread.
  • If skipping bread: yogurt (fermented) is suggested as a better alternative.
  • Beware “diet-style” products that still rely on additives or altered fats to mimic mouthfeel.

Food ingredient/product guidance mentioned

• Sugar-free / “0 sugar” drinks
  • Not necessarily “harmless”: substitute sweeteners are not natural sugars, and effects are still debated.
  • If someone insists on soda: occasional regular intake is worse; sugar-free may be the lesser of two evils—but overall reduce frequency.
• “Diet” or “reduced sugar” may still affect people differently
  • Efficacy/health impact is not always equal to natural-food benefits.
• Olive oil selection
  • Prefer extra virgin olive oil (best quality; extracted with lower-temperature/less harsh processing).
  • Avoid overexposure to heat/light (quality degrades).
• Milk
  • Milk can be nutritious, but the fat type matters.
  • If choosing: avoid excessive saturated fat → choose lower-fat when needed.
• Keto / very low-carb diets
  • Can help some outcomes (e.g., weight control), but may be risky long-term for general use:
    • Higher fat/protein load may stress liver/kidney function over time (as framed in the talk).
  • Not ideal for everyone (e.g., children; some may need more diverse nutrients).

Supplements & “modern wellness products” skepticism

• NMN / probiotics / similar health supplements
  • Not dismissed entirely, but the speaker emphasized limits of evidence and “magical” marketing claims.
  • For probiotics:
    • The gut microbiome is complex; taking only a small number of strains may not guarantee large effects.
    • Benefits are hard to generalize because research varies and outcomes depend on many variables.
• “Superfoods” concept
  • Superfoods were framed as colorful whole plants and vitamin-rich fruits (e.g., citrus).
  • Emphasis: it’s more about whole-food patterns than single magical products.
• Organic food
  • Organic isn’t automatically dramatically healthier for everyone.
  • There may be differences (farming practices, regulation), but overall nutritional differences may be small; it’s more a value/preference choice than a necessity.
• Antibiotics
  • Don’t take them “just in case” for minor illnesses.
  • Let the body build natural resilience; use antibiotics only when appropriate (as described).

Presenters / sources

• 張志強教授 (Prof. Zhang Zhiqiang) — 中大食品及營養科學教授 / Food science expert (Chinese University of Hong Kong interview)