July 30, 2026, 11:02 am | Read time: 4 minutes
The first 1,000 days of life are considered crucial for brain development. But can the amount of sugar consumed during this time affect how healthy the brain remains in later life? An unusual study provides new insights into this question—using a historical event that is rarely available to researchers today.
A Historical Event Made the Study Possible in the First Place
During and after World War II, sugar was strictly rationed in the United Kingdom. When the restrictions were suddenly lifted in September 1953, sugar consumption increased significantly in a short period. This shift allowed researchers to compare people who spent their early years with little sugar to those born shortly after.
46 Percent Lower Risk of Alzheimer’s
People who were exposed to sugar rationing in the womb and during their first two years of life were less likely to develop dementia and Alzheimer’s later. Compared to participants without sugar rationing, their risk of dementia was 27 percent lower, and their risk of Alzheimer’s was even 46 percent lower.
Structure and Process of the Study
Previous studies have already suggested that nutrition in the early years of life can have long-term health effects.1 But how significant is the role of sugar?
This is precisely the question researchers at Guangzhou Medical University in China pursued. The study focused on the first 1,000 days of life—from pregnancy to about the second birthday. During this phase, the brain develops particularly rapidly and is sensitive to external influences, including nutrition.2
The data from 60,394 participants in the UK Biobank, a long-term British database, who were born between 1951 and 1956, were analyzed. Depending on their birth date, the scientists assigned them to one of three groups: people affected by sugar rationing only in the womb, those whose first two years also fell into this period, and participants born after the end of rationing.
Researchers then compared how often participants developed dementia, Alzheimer’s, Parkinson’s, depression, or anxiety disorders later in life. Additionally, they evaluated MRI scans of the brain for some participants. They examined whether the brain appeared biologically older or younger than the actual age and whether there were differences in key brain regions such as the hippocampus, important for learning and memory, or the thalamus, a central hub for processing information in the brain.
Depression and Anxiety Disorders Also Occurred Less Frequently
The connection was not only evident in dementia and Alzheimer’s. Participants with lower sugar exposure in the first 1,000 days of life also had an 11 percent lower risk of depression and a 20 percent lower risk of anxiety disorders. However, the researchers found no comparable link for Parkinson’s.
The results were particularly pronounced when sugar restrictions continued after birth. If they only existed during pregnancy, there were few differences, except for the lower risk of anxiety disorders.
Not only did the researchers find anomalies in diseases, but the MRI scans also suggested that early sugar intake might have long-term effects on the brain. Using a computer model, the scientists estimated the biological age of the brain. For participants exposed to less sugar after birth, this was on average 0.39 years lower.
Furthermore, the researchers found differences in several deep brain regions. The hippocampus, important for learning and memory, and the thalamus, a central hub for processing information, were larger than in participants without early sugar restrictions.
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Why Might the Early Years Be So Important?
Researchers suspect that the brain is particularly susceptible to influence during this time. It develops rapidly and is sensitive to external influences—including nutrition. High sugar intake could adversely alter metabolism and promote inflammatory processes in the long term. Both are already considered potential risk factors for dementia.
The larger brain regions and slightly lower biological brain age could be related to the lower risk of disease. However, this cannot be conclusively determined from the study. The MRI findings only provide initial clues as to how the observed connections might arise.
According to the authors, the results suggest limiting added sugar during pregnancy and the early years of life as much as possible. At the same time, they emphasize that a single study is not enough to fundamentally change existing dietary recommendations.
Strengths and Weaknesses of the Study
The study has several strengths. With just over 60,000 participants, it includes a very large study population. Additionally, the researchers utilized an extraordinary historical situation, which is significantly more informative than many traditional nutrition studies. Since sugar rationing was government-mandated, it did not depend on the participants’ behavior.
Nevertheless, the study has important limitations. The researchers could not determine how much sugar the individual mothers or children actually consumed. The classification was based solely on the birth date during or after sugar rationing.
Moreover, other living conditions in post-war Britain changed after the end of rationing. Despite statistical adjustments, such influences cannot be completely ruled out.