What to Eat to Beat Depression: Dr. Uma Naidoo on Why Food Can Be a Game Changer

Dr. Uma Naidoo has long been passionate about the power of food. Growing up, she would watch her maternal grandmother cook with vegetables picked from the garden and healing spices native to their Indian heritage. Surrounded by adults who were steeped in cooking, wellness, and medicine, including her mother who is a doctor, and aunts and uncles, some who were allopathic doctors with a few Ayurvedic practitioners, Dr. Naidoo said she was submerged in an 'ongoing science discussion, and also an environment of a mind-body connection.”Dr. Naidoo carried this holistic view into adulthood. When she began to study psychiatry, she wondered why nutrition didn't play a greater role in mental health medicine. The focus was solely on medication and therapy, both of which she recognizes as vital but not 'the only tools that we should be having in our toolkit.” So she began to explore how food informs our moods and mental wellbeing.Today Dr. Naidoo is a pioneer in the field of nutritional psychiatry, a burgeoning clinical practice that looks at the impact of food on cognitive function. She founded and directs the Nutritional and Lifestyle Psychiatry Service at Massachusetts General Hospital, the first hospital-based clinic of its kind, and is a trained chef (inspired by Julia Child) and nutritionist.As Dr. Naidoo's work and life attest, food has immense power in our lives…and it can transform our mental health. 'When your doctor says you should eat salad or the color of the rainbow, there's science backing up why we should be doing that,” she says. We recently called her to discuss the food-mood connection, her recent book, This Is Your Brain on Food, and what we need to eat to beat depression and anxiety.

Why is the food-mental health connection so important?

The emerging evidence in the last decade and a half around the the gut-brain connection, and the microbiome has helped us understand the food-mood connection. And what I felt…and feel…that has been missing in the conversations that we have with our clinicians and our doctors is that we're talking about lots of things…family history, diabetes, COVID…but no one is bringing the brain into the conversation. And without the brain, arguably, the rest of our body does not function. So this connection between the brain and food is critical and is one of the things we should be paying attention to.

How are the brain and the gut connected?

What I bring forward is the research around the gut microbiome. The gut and brain are different parts of the body, but they arise from the same cells in the embryo, from which they divide apart to form the different organs. But they remain connected throughout life by the tenth cranial nerve, which is the Vagus Nerve, or often called the ‘Wandering Nerve.' The Vagus Nerve is like a two-way messenger between the two organs…the brain and the gut…that is aligned to send chemical messages 24-7, 365-days-a-year. When our food has been digested, the food breakdown products interact with the gut microbes. Those breakdown products can either be toxic (when we're having less healthy meals) or positive (when we're eating healthy meals).How this also ties in with the brain is that 90 percent of our serotonin receptors are in the gut, and a good portion of our neurotransmitters are also made in the gut. So with our serotonin being in the gut environment, the receptors being there, and the connection back to the brain, we have this understanding that what we eat and the breakdown of those food products can then either help settle our GI system, or it can lead to inflammation over time. If you're consuming more of a fast-food diet, then the breakdown products of your food are going to be less healthy, and over time that sets up for inflammation.

It seems that inflammation has been coming into the conversation more–

Inflammation has been seen as an underlying mechanism, or a fault factor, that is related to so many mental health problems these days.

Where should we start to lean into eating for better mental health?

That's exactly it: It's leaning towards. It's an adjustment. It's tweaking what you're eating today to include more of certain foods and understanding that it's not an overnight fix or cure. This is something that is…ultimately the way that I work with people…a lifestyle change and meant to be sustainable. If you start with the small habit, which is sustainable, you are more likely to stay with it. The moments my patients start to feel a little bit better they want to do more.

What specific foods are best for promoting brain health and eating depression and anxiety?

I group it into categories:One big category includes the color of the rainbow combined with leafy greens. The plant polyphenols have different colors, and the more colors the better because that brings biodiversity back to the gut microbes, which is something they thrive on. Lean into those rainbow-colored vegetables and leafy greens. Leafy greens are rich in folate, which is a very important nutrient in mood because low folate levels are associated with depression. Having four to five daily servings of leafy greens in the diet is important.In this category, I also include prebiotic foods and fermented foods. Prebiotic foods are simple foods in our diet, like the allium family…garlic, leeks, onions…and other foods including bananas and oats. Fermented foods are generally made from vegetables. They included pickled vegetables like kimchi, fermented soybean paste, called miso, or kefir if you eat dairy. Fermented foods are also critical to that gut environment. This is a big category, but it's a good way to start increasing the number of plants in your diet, increasing the color in your diet, increasing the servings of leafy greens, and understanding the importance of those prebiotic and fermented foods.Another category is omega fatty acids. These can be obtained from fatty fish like salmon, anchovies, and sardines. It can also be obtained from plant-based sources like chia seeds, flax seeds, and algae.The third category I include mention is spices. This is often an overlooked ingredient in our kitchens. We add spices, but we don't often realize their power. Start by adding turmeric with a pinch of black pepper to your tea, soup, or super smoothie. These have a good amount of evidence for the improvement of depression. The piperine in black pepper makes the curcumin in turmeric more bioavailable to the brain and body. This is an easy hack that one should try.The fourth category is dark chocolate. Now, in general, I always talk about the 80-20 rule: None of us is perfect. You obviously want to enjoy lots of things. But having our palette become friendlier to darker, more natural chocolate is better than a lot of the sweet dessert options. And added/refined sugar is a huge problem in our diets. Dark natural chocolate is associated with improvement in cognitive health. Cocoa flavanols, which are extremely good for our brain. Analysis shows that eating one to two squares daily of extra dark natural chocolate is potentially very helpful for our mood.

Do you feel this information helps people become more aware of the power of food?

It makes it interesting. I try to include the description of these foods because I want to show people how simple they are. I want to bring them to the fact that when your doctor says you should eat salad or the color of the rainbow, there's actually science backing up why we should be doing that. It's not just, oh, eat dark chocolate because it's good for. But rather, eat dark chocolate because it has been shown to improve cognitive health and to improve mood.

It's common to eat in a hurry, whether it be on the go, standing up, or at our desks. Does how we eat impact our health?

I certainly believe so because I believe in the mind-body connection. I believe in mindful eating with intention, being grateful for the ingredients. As a chef you are taught to respect your ingredients and I feel strongly about that. Trust me, I've been there. As a resident doctor in training, I was always eating on the run, missing a meal, trying to get by on lots of coffee. I've been on my own journey of learning that that is not the best for my body. So being mindful is something I've driven in.Also, it's important to not be regretful of a meal that you eat. Say you do eat something that you later realize was slightly unhealthy. Rather than regret it, the idea is to move on and correct at the next meal. Realizing that how you eat and the intention that you have is all-important.Dr. Uma Naidoo is a Harvard trained nutritional psychiatrist, professional chef and nutrition specialist & author of the national bestseller: This is Your Brain on Food. Learn more at umanaidoomd.com.