多吃植物與降低失智風險相關，即使晚年也有效
Eating More Plants Linked to Lower Risk of Dementia, Even in Older Age
根據一項最新研究，攝取包含全穀物、蔬菜和水果的高品質植物性飲食，可能有助於預防認知障礙——即使人們在50多歲甚至60多歲的晚年才開始這種飲食習慣也同樣有效。
Eating a high-quality plant-rich diet that includes whole grains, vegetables and fruits may prevent cognitive impairment — even when people start that diet in their late 50s and 60s, according to a new study.
該研究的資深作者、夏威夷大學癌症中心的人口科學教授林恩熙（Unhee Lim，音譯）在電子郵件中表示：「開始健康飲食以降低阿茲海默症及相關失智症的風險，永遠不嫌晚。」
“It’s never too late to start eating healthy to lower the risk of Alzheimer’s disease and related dementias,” said senior author Unhee Lim, a professor of population sciences at the University of Hawaii Cancer Center in Honolulu, in an email.
林教授指出，在十年的時間裡，減少攝取多種不健康食物的年長者，與飲食習慣沒有改變的成人相比，罹患阿茲海默症和失智症的風險降低了 11%。
Older adults who cut many unhealthy foods from their diet over a decade had a 11% lower risk of Alzheimer’s and dementia when compared with adults whose diets didn’t change, Lim said.
然而，如果人們在十年內攝取越來越多不健康的植物性食品，例如精製穀物和含有添加糖的食物，那麼在十年結束時，他們罹患某種失智症的可能性要高出大約 25%。
However, people who increasingly ate more unhealthy plant-based options, such as refined grains and foods with added sugars, were about 25% more likely to develop some type of dementia at the end of 10 years, she said.
未參與該研究的預防與生活方式醫學專家大衛·卡茲（Dr. David Katz）博士表示：「這些發現表明，以植物為主的飲食和高品質的膳食結構，皆有助於在我們衰老時保護大腦功能。」卡茲是免營利組織「真實健康倡議」（True Health Initiative）的創始人，該組織是一個致力於推廣實證生活醫學的全球專家聯盟。
“The findings suggest that both plant-predominant eating and high diet quality help protect brain function as we age,” said Dr. David Katz, a specialist in preventive and lifestyle medicine who was not involved with the study. Katz founded the nonprofit True Health Initiative, a global coalition of experts dedicated to evidence-based lifestyle medicine.
🥗 植物性飲食的廣義定義與陷阱
The Broad Definition and Pitfalls of a Plant-Based Diet
植物性飲食的基本定義非常廣泛，僅要求個人優先攝取植物性食物，而非肉類、牛奶和蛋等動物產品。在這個傘形概念下，一個人可以自稱為純素食者（vegan），卻依然依賴已知有害健康的含糖、富含脂肪且超加工的食品維生。
The basic definition of a plant-based diet is broad, simply requiring a person to prioritize eating more plant foods than animal products such as meat, milk and eggs. Under that umbrella, a person could call themselves a vegan and yet subsist on sugary, fat-filled, ultraprocessed foods known to harm health.
例如，早餐可能是一個超加工的冷凍鬆餅或薄煎餅，淋上人工合成的楓糖漿；午餐可能包含高鈉的速食植物肉漢堡、飽含飽和脂肪的炸薯條或洋蔥圈，以及一瓶裝滿糖的果汁汽水；晚餐則可能吃由精製白麵粉製成的義大利麵，搭配高糖番茄醬，隨後再來些超加工餅乾或蛋糕——雖然這一切都是「植物性」的，但對您的大腦健康毫無益處。
Breakfast, for example, could be an ultraprocessed frozen waffle or pancake with fake maple syrup. Lunch could include a fast-food veggie burger high in sodium, french fries or onion rings dripping in saturated fat, and a fruit-based soda packed with sugar. Dinner could include refined-grain white flour pasta with high-sugar tomato sauce, followed by ultraprocessed cookies or cake — all plant-based, but none good for your brain’s health.
🔍 研究三大核心發現
Three Key Findings of the Study
1. 大腦保護傘：高品質健康植物食譜
Finding 1該研究將飲食劃分為三種品質等級，其中最頂層的是最健康的植物性食物——包括全穀物、水果、蔬菜、植物油、堅果、豆類以及茶和咖啡。研究小組發現，多攝取這類健康植物最能保護大腦。在攝取最健康植物性食品的亞組中，攝取最多健康植物的人比攝取最少的人，失智風險降低了 7%。
The research team scored diets on three tiers of quality. The top tier were the healthiest plant foods — whole grains, fruits, vegetables, vegetable oils, nuts, legumes, and tea and coffee. Eating more of these plants was most protective for the brain, the researchers found. When a subgroup of people who ate the healthiest plant-based foods were compared with each other, those who ate the most plants in this tier lowered their risk of dementia by 7% compared with those who ate the least.
2. 隱形殺手：低品質精製植物食物的風險
Finding 2高於動物性脂肪的第二層級，是較不健康的植物性食品，例如精製穀物、果汁、馬鈴薯和添加糖。在攝取較多不健康植物選擇的亞組中，攝取量最大的人罹患失智症的機率反而高出 6%。例如，馬鈴薯富含澱粉，在血液中會迅速轉化為葡萄糖，引發血糖飆升；而飲用蘋果汁或柳橙汁會讓血液充斥果糖，不像吃一整顆水果那樣有纖維能減緩果糖釋放。
A tier up from animal fats was less healthy plant-based foods such as refined grains, fruit juices, potatoes and added sugars. Among the subgroup who ate more unhealthy plant choices, those who ate the largest amount had a 6% greater chance of developing dementia, according to the study. Why are fruit juices and potatoes considered less healthy? Potatoes are high in starch, which quickly turns into glucose in the blood, potentially triggering blood sugar spikes. Drinking fruit juice floods the blood with fructose. Eating a whole apple or orange, on the other hand, doesn’t spike blood sugar levels in the same way because the fiber inherent in the fruit slows the release of fructose into the blood.
3. 行動永遠不嫌晚：高齡群體同樣受益
Finding 3該研究發表於《神經學》期刊（Neurology），調查了近 93,000 名平均年齡為 59 歲的多族裔受訪者。夏威夷大學癌症中心副教授朴松伊（Song-Yi Park，音譯）指出：「我們發現，即使從年長時才開始採用植物性飲食，並避免低品質的植物性飲食，也與降低阿茲海默症及其他失智症的風險相關。我們的發現強調，不僅遵循植物性飲食很重要，確保飲食的高品質也同樣關鍵。」
The new report, published in the journal Neurology, included nearly 93,000 people with an average age of 59. “We found that adopting a plant-based diet, even starting at an older age, and refraining from low-quality plant-based diets were associated with a lower risk of Alzheimer’s and other dementias,” said lead author Song-Yi Park, an associate professor of population sciences at the University of Hawaii’s Cancer Center. “Our findings highlight that it is important not only to follow a plant-based diet, but also to ensure that the diet is of high quality,” Park said.
❤️ 心血管與地球健康的雙重紅利
Dual Benefits for Cardiovascular and Planetary Health
除了大腦健康外，先前的研究也顯示，攝取健康的植物性飲食可將糖尿病、心血管疾病及高血壓等代謝風險因素降低高達 68%。反之，攝取較不健康的植物性飲食則與高出 63% 的罹病風險相關。在控制心臟風險方面，限制紅肉並多吃全穀物、豆類和多采多姿的蔬果能降低膽固醇和心血管疾病機率。而在多吃全穀物、新鮮蔬果並限制不健康飲食的人群中，罹患第 2 型糖尿病的風險降低了 24%，同時還能降低身體質量指數（BMI）和腰圍。
Beyond the brain, prior research has shown eating a healthy plant-based diet was associated with up to a 68% lower risk for diabetes, cardiovascular disease, and metabolic risk factors such as high blood pressure. Consuming an unhealthier plant-based diet, however, was associated with up to a 63% higher risk. When it comes to the heart, studies show limiting red meat and eating whole grains, legumes, and a variety of colorful fruits and veggies can lower cholesterol and the risk of cardiovascular disease. The risk of type 2 diabetes was cut by 24% in people who ate the most whole grains, fresh fruits and vegetables, and limited their intake of unhealthy plant and animal foods. The diet also lowered body mass index and waist circumference.
健康的植物飲食也與延長壽命、造福地球息息相關。由16個國家的頂尖科學家組成的 EAT-Lancet 委員會在 2023 年的一份報告中發現，密切遵循以水果、蔬菜和全穀物為主的地球友善飲食（planetary health diet），可降低人類近三分之一的過早死亡風險，同時顯著減少破壞地球的溫室氣體排放。
Eating a healthy plant diet has also been linked to longer life — for both people and the planet. A 2023 report by the EAT-Lancet Commission, composed of leading scientists from 16 countries, found closely following a planet-friendly diet of mostly fruits, vegetables and whole grains reduces the risk of premature death by nearly one-third in people, while also dramatically cutting the release of greenhouse gases devastating the planet.
哈佛大學陳曾熙公共衛生學院的流行病學與營養學教授沃爾特·威利特（Dr. Walter Willett）博士向 CNN 表示：「在我們研究的每一種主要死因中，越遵循地球健康飲食的人，其死亡風險就越低。這些發現顯示，人類健康與地球健康是多麼緊密相連。健康的飲食不僅促進了環境的永續性，而這反過來對於地球上每個人的健康和福祉都至關重要。」
“For every major cause of death we looked at, there was a lower risk in people with better adherence to the planetary health diet,” coauthor Dr. Walter Willett, professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health in Boston, told CNN in a prior interview. “The findings show just how linked human and planetary health are. Eating healthfully boosts environmental sustainability — which in turn is essential for the health and well-being of every person on Earth,” Willett said.