We all have a lot on our minds these days, so it’s natural to have a memory slip once in a while. But a higher body weight can also contribute to fuzzy thinking.
How? Carrying significant weight on your body can lead to a health condition called chronic inflammation. With chronic inflammation, your body continues to send inflammatory signals even when you aren’t healing from an injury or minor illness. That can lead to serious health conditions such as heart disease, diabetes, and cancer — and it can also impact how well your brain functions. (1)
But this doesn’t happen only to higher-weight people. Even people who aren’t overweight can have inflammation in their bodies. “Inflammation can happen in your body, your neighbor’s body, or your co-worker’s body, no matter what their body size is,” says Jerlyn Jones, RDN, owner of Atlanta-based nutrition consulting practice The Lifestyle Dietitian. “Anyone who eats mostly pro-inflammatory foods increases their risk of chronic inflammation in the body.”
Here’s how inflammation can affect the brain, along with what foods you should — and shouldn’t — eat to help keep your mind sharp.
What Brain-Health Issues Can Be Caused by Higher Weight?
Research has connected the dots between inflammation, higher weight, and several memory-related health problems, such as the following issues:
Brain Fog
Have you ever wondered if being overweight can cause brain fog? Well, there is a kernel of truth to it. Brain fog is a label for symptoms that include reduced cognition, trouble concentrating, and a loss of short-term memory, and it can be caused by inflammation in your brain. (2) It can cause a temporary blockage in how well you are able to process information.
“Brain fog is typically associated with systemic inflammatory conditions, and high body fat can increase it,” says Lona Sandon, PhD, RDN, associate professor in the department of clinical nutrition at University of Texas Southwestern Medical Center.
Working Memory
Working memory is the ability to hold and manipulate information in your head. You use it for things that are important to you right now — like where your cell phone is — not things you want to recall two decades from now.
Research shows that higher weight has a negative impact on working memory, even in young adults. According to a 2020 study of people in their twenties and thirties, inflammation plays an important role in the relationship between obesity and working memory. (3) And another study found that higher body mass index (BMI) is associated with periodic memory deficits even in people as young as 18. (4)
Alzheimer’s and Dementia
Inflammation has also been tied to these two serious brain-health conditions. According to a 2023 study (5), systemic inflammation plays a small but significant role in dementia, particularly vascular dementia. Vascular dementia is a decline in thinking skills caused by reduced blood flow to the brain. (6) Obesity is also a risk factor for developing Alzheimer’s disease. (7)
What to Eat to Protect Your Brain Health
While there’s no guarantee that losing weight will boost your brain health, it certainly doesn’t hurt. What can help is following a healthy diet, which may combat inflammation in the body — and you’re likely already doing this on your weight loss journey.
“Overall, good nutrition enhances immunity,” says Isabel Maples, RDN, a nutritionist based in Virginia. “A healthful diet can provide antioxidants that reduce the stress of inflammation.”
To help protect brain health, foods high in vitamins A, C, and D as well as zinc and omega-3 fatty acids should be on your menu, Jones says. Here are specific foods she recommends that people eat more of to help reduce inflammation.
- Vitamin A: Sweet potato, carrots, butternut squash, spinach
- Vitamin C: Kiwi, bell peppers, strawberries, oranges
- Vitamin D: Salmon, mushrooms, fortified milk or milk substitutes, tuna, eggs
- Zinc: Nuts (almonds, pistachios) and seeds (chia, sunflower, flax)
- Omega-3s: Sardines, walnuts
If you’re looking for an eating plan that closely follows the ideas of anti-inflammatory eating, Jones says to consider the Mediterranean diet, which is high in fruits, vegetables, nuts, whole grains, fish, and healthy oils.
Foods to Avoid for Better Brain Health
Fortunately, if you’re already on a weight loss journey, the foods you’re likely eliminating are the ones that can lead to brain-harming inflammation: those high in calories, saturated fat, sugar, and sodium. Jones says to limit the pro-inflammatory foods listed below:
- Partially hydrogenated oils such as shortening, lard, and corn oil
- Refined carbs and sugars such as pastries, white bread, cookies, cakes, pies, ice cream, and sugary cereals
- French fries and other fried foods
- Soda and other sweetened beverages
- Red meat (burgers, steak) and highly processed meats such as bacon, sausage, and hot dogs
Maples notes that other lifestyle tweaks can add to the anti-inflammation equation too. “For better health, experts recommend regular physical activity, getting enough sleep, and maintaining a healthy weight,” she says.
Editorial Sources and Fact-Checking
- Cleveland Clinic. Inflammation.
- Cleveland Clinic. Strategies for Busting Up Brain Fog.
- Yang Y, Shields GS, Wu Q, et al. The association between obesity and lower working memory is mediated by inflammation: Findings from a nationally representative dataset of U.S. Adults. Brain, Behavior, and Immunity. February 2020.
- Cheke LG, Simons JS, Clayton NS. Higher body mass index is associated with episodic memory deficits in young adults. Experimental Psychology Society. November 2016.
- Mekli K, Lophatananon A, Maharani A, et al. Association between an inflammatory biomarker score and future dementia diagnosis in the population-based UK Biobank cohort of 500,000 people. PLOS One. July 19, 2023.
- Alzheimer’s Association. Vascular Dementia.
- Flores-Cordero JA, Pérez-Pérez A, Jiménez-Cortegana C, et al. Obesity as a Risk Factor for Dementia and Alzheimer’s Disease: The Role of Leptin. International Journal of Molecular Sciences. May 6, 2022.
Disclaimer: This article provides general information and discussions about health and related subjects. The information and other content provided on this website or in any linked materials are not intended and should not be considered, or used as a substitute for, medical advice, diagnosis, or treatment.
