An association has been identified between visceral fat and beta-amyloid accumulation in middle-aged people without disease. Abdominal fat promotes brain inflammation, one of the mechanisms underlying dementia
Higher quantities than visceral abdominal fat in the middle age are linked to a greater risk of developing Alzheimer’s second a research just presented at the annual meeting of the Radiological Society of North America (RSNA).
Obesity and Alzheimer’s
I have known for some years that obesity is a significant factor for Alzheimer’s disease: a fact reported in various research. Excess weight can cause neuronal changes such as protein accumulation beta-amyloid or the formation of brain damage generally associated with Alzheimer’s disease.
Which fat is bad for you?
RSNA researchers, however, have made the connection for the first time a specific type of fat (the visceral one) to the accumulation of the beta-amyloid protein in cognitively normal people.
The visceral fat the fat that surrounds the internal organs located deep (hence called visceral) in the belly and not located at a subcutaneous level. According to research, it increases the risk of Alzheimer’s because it is related to changes that occur in the brain up to 15 years before the first symptoms of memory loss of the disease appear.
To demonstrate this, the researchers analyzed the data of 54 cognitively healthy subjects, aged between 40 and 60, with an average Body Mass Index (BMI) of 32 (which determines first degree obesity). Participants underwent measurements of glucose and of theinsulin, as well as glucose tolerance tests. The volume of subcutaneous fat and visceral fat were measured using abdominal MRI. The brain MRI instead measured the cortical thickness of the brain regions that are usually affected by Alzheimer’s disease. Finally, PET (positron emission tomography) was used to examine the presence of in the brain amyloid plaques and tau tanglesproteins that are believed to interfere in communication between brain cells and are detected in large quantities in the brains of people suffering from Alzheimer’s.
The more visceral fat, the more amyloid
Scientists have discovered that a higher proportion of visceral fat (compared to subcutaneous fat) was associated, in the subjects examined, with one higher concentration of amyloid (highlighted by PET) in an area of the cerebral cortex known to be the site of amyloid accumulation in Alzheimer’s. This relationship was worse in men than in women, given that men physiologically tend to accumulate fat in the belly, while women do so after menopause.
The researchers also found that higher measurements of visceral fat correlated with increased fat load
inflammation in the brain.
Simplifying, given the same body mass index, and therefore the degree of obesity, the state of the brain (with regards to the accumulation of proteins which can determine future risk of Alzheimer’s) was worse in people with a greater share of visceral fat compared to subcutaneous fat.
By going beyond body mass index and better characterizing the anatomical distribution of body fat on MRI, we now have a better understanding of why this factor may increase the risk of Alzheimer’s disease, said the study’s senior author, Dr. Cyrus A. Raji, Associate Professor of Radiology and Neurology and Director of Neuromagnetic Resonance at the Mallinckrodt Institute of Radiology (MIR) at Washington University School of Medicine in St. Louis. “Several factors are assumed to play a role,” said MIR researcher Dr. Mahsa Dolatshahi: “The inflammatory secretions of visceral fat, as opposed to the potentially protective effects of subcutaneous fat, can lead to inflammation in the brain, one of the main mechanisms that contribute to Alzheimer’s disease.
The two types of fat
Subcutaneous fatin fact, which women tend to accumulate on the hips and thighs, has a protective effect against heart attacks and strokes and anti-inflammatory at the brain level. For this reason, until menopause, women suffer less than men from a series of pathologies.
Visceral fat placed on the abdomen instead dangerous: covers internal organs (such as liver, heart and vessels), can produce substances pro-inflammatory and pro-tumor and increases the risk of cardiovascular disease, sexual dysfunction, kidney problems and some cancers.
The belly is dangerous even in thin subjects
For this reason the advice is to return as soon as possible ideal weight if you are overweight, but not only: a belly is dangerous even in thin people. A previous study published in JAMA found that menopausal women with normal weight but excess abdominal fat had a 31% greater risk of all-cause death. The risk was almost the same as in the obese group. That’s why it’s important eliminate the bacon for everyone: not just a blemish, a source of numerous health problems.
The optimal abdominal circumference for women is less than 80cm, there is abdominal obesity with more than 88 cm; for men they are 94cm and 102 (How to lose your belly after 50? See the article below, ed).
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November 21, 2023 (changed November 21, 2023 | 07:20)
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