Following low-calorie diet could make you depressed, major study finds
重大研究发现：低热量饮食或致抑郁
A new study has found that following a low-calorie diet could increase the risk of developing symptoms of depression. The researchers found that the effects of calorie restriction on mood were more pronounced in men and overweight people.
一项新研究发现，遵循低热量饮食可能会增加出现抑郁症状的风险。研究人员发现，卡路里限制对情绪的影响在男性和超重人群中更为明显。
These findings stand in contrast to previous studies which claim low-calorie diets improve depressive symptoms. However, the researchers noted that prior trials included tailored and balanced diet programmes that may not be the same as what people realistically follow in everyday life.
这些发现与先前声称低热量饮食可改善抑郁症状的研究相悖。不过，研究人员指出，先前试验采用的是定制且均衡的饮食方案，可能与人们在现实生活中实际遵循的饮食不同。
For the study, published in BMJ Nutrition Prevention & Health, researchers in Canada used data from the 28,525 people who took part in the US National Health and Nutrition Examination Survey (NHANES) and had completed a health questionnaire relating to depressive symptoms, which gave them a score based on severity.
这项研究发表在《英国医学杂志–营养预防与健康》上，加拿大研究人员使用了美国国家健康与营养检查调查（NHANES）中28525人的数据，这些人都完成了与抑郁症状相关的健康问卷，根据抑郁症状的严重程度给出了相应分数。
Of the total, 14,329 were women and 14,196 were men. A little under 8 per cent had reported depressive symptoms, while 33 per cent were overweight and 38 per cent were obese.
在这些人中，女性有14329人，男性有14196人。略低于8%的人报告有抑郁症状，33%的人超重，38%的人肥胖。
The majority of the group (87 per cent) said they were not on a specific diet, while 2,206 were restricting calories. Some 859 were on a “nutrient-restrictive” diet, low in fat, sugar, salt, fibre or carbohydrate, and 631 were on diets tailored for the likes of diabetes.
大部分人（87%）表示没有遵循特定饮食，而2206人在限制卡路里摄入。约859人遵循“营养限制性”饮食，即低脂肪、低糖、低盐、低纤维或低碳水化合物饮食，631人遵循针对糖尿病等疾病的定制饮食。
Researchers found low-calorie diets were more common among obese patients and those who were overweight. Questionnaire scores for depressive symptoms, such as a low mood, low energy and sleep disturbances, were higher among those restricting calories compared to those who reported not being on a diet at all. The scores were also higher among overweight people following low-calorie diets.
研究人员发现，低热量饮食在肥胖患者和超重人群中更为常见。与那些表示完全没有节食的人相比，限制卡路里摄入的人在抑郁症状问卷（如情绪低落、精力不足和睡眠障碍）上的得分更高。遵循低热量饮食的超重人群，问卷得分也更高。
Researchers said: “Numerous studies have consistently focused on ‘healthy’ versus ‘unhealthy’ diets. They have shown that ‘healthy’ diets rich in minimally processed foods, fresh fruits and vegetables, whole grains, nuts, seeds, lean proteins and fish have been linked to a lower risk of depression.”
研究人员表示：“众多研究一直聚焦于‘健康’饮食与‘不健康’饮食。研究表明，富含未深度加工食品、新鲜水果和蔬菜、全谷物、坚果、种子、瘦肉蛋白和鱼类的‘健康’饮食，与较低的抑郁风险相关。”
In contrast, an ‘unhealthy’ diet dominated by ultra-processed foods, refined carbohydrates, saturated fats, processed meats and sweets is associated with an increased risk of depressive symptoms.
相反，以超加工食品、精制碳水化合物、饱和脂肪、加工肉类和甜食为主的“不健康”饮食，则与抑郁症状风险增加有关。
Therefore, individuals must adopt a perfectly healthy dietary pattern to reduce the risk of depressive symptoms. This dichotomy fails to capture the complexity of real-world eating habits.
因此，个人必须采用绝对健康的饮食模式，以降低出现抑郁症状的风险。但这种非此即彼的观点，未能考虑到现实饮食习惯的复杂性。
Restricting calories can lead to deficiencies in protein, vitamins and minerals, researchers suggest, which puts the body under stress. The findings also contradict previous studies showing low-calorie diets improve depressive symptoms. Researchers highlight that these studies were controlled trials, with those taking part following carefully designed and balanced diets.
研究人员提出，限制卡路里摄入可能导致蛋白质、维生素和矿物质缺乏，使身体承受压力。研究结果也与先前表明低热量饮食可改善抑郁症状的研究相矛盾。研究人员强调，先前的研究是受控试验，参与者遵循精心设计且均衡的饮食。
The team said a focus on “idealised diets” can “overlook the diversity of dietary patterns”, adding: “In contrast, real-life calorie-restricted diets and obesity often result in nutritional deficiencies, particularly in protein, essential vitamins and minerals, and induce physiological stress, which can exacerbate depressive symptomatology including cognitive-affective symptoms.”
研究团队表示，关注“理想化饮食”可能会“忽视饮食模式的多样性”，并补充道：“相比之下，现实生活中的限制热量饮食和肥胖往往会导致营养缺乏，尤其是蛋白质、必需维生素和矿物质缺乏，还会引发生理压力，这可能会加重抑郁症状，包括认知情感症状。”
Researchers stressed the study has a number of limitations, but gives an insight to how diets recommended by healthcare professionals should be considered for risk factors for depression, especially in men and obese patients.
研究人员强调，这项研究存在一些局限性，但它为思考医疗保健专业人员推荐的饮食如何作为抑郁风险因素提供了见解，尤其是在男性和肥胖患者中。
Professor Sumantra Ray, chief scientist and executive director of the NNEdPro Global Institute for Food, Nutrition and Health, which co-owns BMJ Nutrition Prevention & Health with BMJ Group, added: “This study adds to the emerging evidence linking dietary patterns and mental health, raising important questions about whether restrictive diets which are low in nutrients considered beneficial for cognitive health, such as omega-3 fatty acids and vitamin B12, may precipitate depressive symptoms.”
NNEdPro全球食品、营养与健康研究所（与英国医学杂志集团共同拥有《英国医学杂志–营养预防与健康》）的首席科学家兼执行董事苏曼特拉·雷教授补充说：“这项研究为饮食模式与心理健康之间的关联提供了新证据，引发了一个重要问题：那些限制摄入被认为对认知健康有益的营养素（如欧米伽-3脂肪酸和维生素B12）的限制性饮食，是否会引发抑郁症状。”
“But the effect sizes are small, with further statistical limitations limiting the generalisability of the findings. Further well designed studies that accurately capture dietary intake and minimise the impact of chance and confounding are needed to continue this important line of inquiry.”
“但效应量较小，且存在进一步统计局限性，限制了研究结果的普适性。后续需要设计更完善的研究，准确记录饮食摄入情况，并尽量减少偶然因素和混杂因素的影响，以继续推进这一重要研究领域。”
