May 2020 Issue
Brain Health: Nutrition Care After Concussion
By Jamie Santa Cruz
Vol. 22, No. 5, P. 12
What the Science Says About Micronutrient Intake and Brain Recovery
When a patient suffers a concussion, doctors typically recommend rest as the top priority in treatment. Both physical and cognitive rest are crucial for allowing the brain to heal. But what about the role of nutrition following a concussion? Can a patient’s diet and intake of micronutrients influence his or her recovery? Research on this question is still at an early stage, but there’s emerging evidence suggesting that nutrition could indeed make a difference.
Stats and Symptoms
Although the word “concussion” commonly is used in everyday speech, the preferred term for this type of head injury is “mild traumatic brain injury” (mTBI). According to Rebecca Denniss, MSc, a doctoral researcher in cognitive neuroscience at Sheffield Hallam University in Sheffield, England, the latter term is favored because it more accurately reflects the seriousness of the injury. “‘Concussion’ sounds like a very mild thing,” she says.
Each year, there are approximately 2.5 million emergency department visits in the United States for TBI, and the great majority of these represent mild injuries (ie, concussions).1 However, the total number of concussions is significantly higher than this, as many people with concussion don’t seek treatment or report their injuries.2,3
For most adults, the top causes of mTBI are falls and motor vehicle accidents, but sports-related concussions are increasingly another topic of concern.3,4 Symptoms include headache, a feeling of fogginess, sensitivity to light or sound, irritability, and sleep disturbances. These symptoms typically last only seven to 10 days in adults, but they can take several weeks to resolve.5 There’s also growing concern about potential long-term consequences of mTBI, including increased risk of future concussion, dementia, and stroke, among other issues.5-7
The Biochemical Cascade
The impact of mTBI sets off a secondary biochemical cascade within the brain. Denniss says, “It’s this secondary biochemical cascade that causes the majority of the problems that people experience in terms of their brain function. So, from my perspective, the purpose of improving diet is to impact on this secondary biochemical cascade.”
What exactly occurs in this biochemical cascade that may warrant a nutritional intervention? To begin with, the impact of the trauma disrupts neuronal cell membranes and causes a stretching of axons (nerve fibers) in the brain. These changes interfere with the normal regulation of the flow of potassium and calcium ions in the brain and prompt the release of excitatory neurotransmitters such as glutamate. In its efforts to reestablish equilibrium, the brain rapidly depletes its energy stores and is forced into a hypermetabolic state. This leads to the overproduction of oxygen radicals, causing oxidative stress.
At the same time, a neuronal inflammatory response begins soon after injury. This response can continue for several weeks, and eventually it can damage cell membranes if it becomes severe enough. The collection of these processes—the brain’s hypermetabolic state, oxidative stress, and inflammation—can result in the death of neuronal cells, ultimately causing an impact on cognition.
Omega-3 Fatty Acids
The most extensive evidence regarding the benefits of a nutritional intervention after mTBI lies with omega-3 fatty acids, Denniss says. There’s a strong scientific rationale to support the importance of omega-3s—especially DHA. DHA phospholipids are a key component of the central nervous system membranes, and changes to the DHA composition of the membranes impacts axonal stability, neuronal plasticity, glucose uptake, and neuroinflammation.8 Thus, DHA could directly impact several aspects of the neuromolecular processes that occur in the wake of mTBI.
Multiple animal studies have found a neuroprotective benefit of omega-3 supplementation after mTBI.9 One rat model found that daily DHA intake for 30 days after mTBI reduced markers of axonal injury.10 Another rat model looked at supplementation with fish oil (which contains both DHA and other omega-3s) and likewise found that supplementation for 30 days reduced injury to axons.11 A third study of rats with mTBI tested the effects of a combination supplement containing DHA as well as resveratrol and prebiotic fiber, and it found that rats that received the supplement had fewer longer-term deficits following their injury.12 Other animal studies have found that omega-3 supplementation before mTBI also protects from injury and improves recovery.9
Unfortunately, there are currently no randomized controlled trials of omega-3s for the treatment of mTBI in humans.8 One randomized controlled trial of collegiate football players found that supplementation appeared to protect against sports-related axonal injury. However, the study didn’t investigate mTBI; rather, it examined subconcussive trauma and was limited to participants without known TBI.13
Protein: Branched-Chain Amino Acids and Creatine
Several studies have looked at branched-chain amino acids (BCAAs) and their impact on TBI. BCAAs consist of the essential amino acids isoleucine, leucine, and valine, found in meats, dairy, beans, nuts, corn, and some grains. These amino acids are important for the synthesis of neurotransmitters and have a role in maintaining the balance between excitatory and inhibitory neurotransmitters (a balance that’s thrown off in TBI). Research has found that levels of BCAAs are lower in humans after TBI compared with controls, suggesting that the neuromolecular cascade that occurs in a TBI affects levels of these amino acids.14 Several studies in animal models of mild-to-moderate TBI and humans with severe TBI have found that BCAA supplementation after TBI provides a cognitive benefit.15-18 However, there are no studies of BCAAs in humans with mTBI, so it’s unclear whether the same benefits extend to humans with less serious injuries.
Other studies have examined supplementation with creatine, an amino acid synthesized in the liver, kidneys, and pancreas, which also can be obtained from food. It’s used as an energy source in the central nervous system, so the theory is that supplementation could help replenish energy stores in the brain and thereby prevent the negative impacts of the hypermetabolic state induced by TBI. Limited research in rodents, plus one study of severe TBI in children, support this theory.14 However, some of these studies looked at supplementation before the injury (rather than afterward), and again, it’s unclear whether the benefits seen in moderate to severe TBI would translate to mTBI.
Other Supplements and Dietary Patterns
Various research has examined other supplements for their potential neuroprotective benefits after TBI. Among these supplements are curcumin (a phytochemical in turmeric), resveratrol, melatonin, magnesium, and vitamins B2, B3, C, D, and E.14,19 In addition, some research has examined the impact of calorie restriction after TBI.20-22 Researchers surmise there’s scientific reason to believe these supplements should offer potential benefits after TBI in humans.23 Results from experimental animal studies and a handful of studies in humans with severe TBI strengthen this hypothesis. However, there are no studies using these interventions in humans with mTBI. Therefore, at least two recent reviews have called for a cautionary stance with regard to supplements for treatment of mTBI because they haven’t yet been proven effective.14,19
Recommendations for RDs
According to Angel Planells, MS, RDN, a dietitian in private practice in Seattle and a spokesperson for the Academy of Nutrition and Dietetics, patients may struggle with eating immediately after mTBI due to nausea, in which case a bland diet temporarily may be necessary. However, Planells recommends focusing on a quality diet as much as possible. “Diet can help both in the short and long term. We need to get fuel to the body quickly despite some of the gastrointestinal distress (nausea, vomiting) symptoms that may be present.”
Although there’s insufficient evidence to recommend specific supplements following mTBI, Planells and Denniss make the following sensible dietary recommendations:
• Avoid inflammatory foods. “People after head injury need to try to avoid inflammatory foods—like highly processed/refined foods, red meat, alcohol—and eat more unprocessed foods,” Denniss says. Regarding alcohol specifically, red wine could be considered an anti-inflammatory, but Denniss recommends avoiding even this form of alcohol, on the grounds that all types of alcohol can further impair cognitive problems and negatively impact mood—“essentially all the things alcohol does normally but amplified as the brain is in a sensitive state post injury,” Denniss says. Instead of processed foods, Denniss recommends fresh fruit and vegetables, especially green leafy vegetables. “Green leafy vegetables are very good because they have a lot of the vitamins and minerals” that may be important in head injury recovery.
• Aim for a higher ratio of omega-3s to omega-6s. When selecting oils, Denniss suggests reducing intake of sunflower and corn oils. “These are all high in omega-6s,” she says. Instead, she recommends olive oil, which is lower in omega-6s and higher in omega-3s, or perhaps soybean oil, which is high in omega-6s but also relatively high in omega-3s.
• Ensure adequate protein. “It’s important that we try to focus on some quality sources of protein, be it animal/vegetable protein, eggs, nuts, seeds, beans, and dairy,” Planells says. In addition to its potential cognitive benefits, “protein also aids in our cellular and tissue production/repair. If we’re working with an athlete, it’s really important to minimize muscle mass loss and maintain their weight.” The best bet? Encourage intake of fatty fish and omega-3–rich eggs. “[These] will help combine quality protein with essential fatty acids,” Planells says.
— Jamie Santa Cruz is a health and medical writer in the greater Denver area.
1. TBI-related emergency department (ED) visits. Centers for Disease Control and Prevention website. https://www.cdc.gov/traumaticbraininjury/data/tbi-ed-visits.html. Updated March 29, 2019.
2. Torres DM, Galetta KM, Phillips HW, et al. Sports-related concussion: anonymous survey of a collegiate cohort. Neurol Clin Pract. 2013;3(4):279-287.
3. Daneshvar DH, Nowinski CJ, McKee AC, Cantu RC. The epidemiology of sport-related concussion. Clin Sports Med. 2011;30(1):1-17.
4. Mullally WJ. Concussion. Am J Med. 2017;130(8):885-892.
5. Barrett EC, McBurney MI, Ciappio ED. ω-3 fatty acid supplementation as a potential therapeutic aid for the recovery from mild traumatic brain injury/concussion. Adv Nutr. 2014;5(3):268-277.
6. Barnes DE, Byers AL, Gardner RC, Seal KH, Boscardin WJ, Yaffe K. Association of mild traumatic brain injury with and without loss of consciousness with dementia in US military veterans. JAMA Neurol. 2018;75(9):1055-1061.
7. Liu SW, Huang LC, Chung WF, et al. Increased risk of stroke in patients of concussion: a nationwide cohort study. Int J Environ Res Public Health. 2017;14(3):230.
8. Gupta A, Summerville G, Senter C. Treatment of acute sports-related concussion. Curr Rev Musculoskelet Med. 2019;12(2):117-123.
9. Trojian TH, Jackson E. Ω-3 polyunsaturated fatty acids and concussions: treatment or not? Curr Sports Med Rep. 2011;10(4):180-185.
10. Bailes JE, Mills JD. Docosahexaenoic acid reduces traumatic axonal injury in a rodent head injury model. J Neurotrauma. 2010;27(9):1617-1624.
11. Mills JD, Bailes JE, Sedney CL, Hutchins H, Sears B. Omega-3 fatty acid supplementation and reduction of traumatic axonal injury in a rodent head injury model. J Neurosurg. 2011;114(1):77-84.
12. Salberg S, Yamakawa G, Christensen J, Kolb B, Mychasiuk R. Assessment of a nutritional supplement containing resveratrol, prebiotic fiber, and omega-3 fatty acids for the prevention and treatment of mild traumatic brain injury in rats. Neuroscience. 2017;4(365):146-157.
13. Oliver JM, Jones MT, Kirk KM, et al. Effect of docosahexaenoic acid on a biomarker of head trauma in American football. Med Sci Sports Exerc. 2016;48(6):974-982.
14. Trojian TH, Wang DH, Leddy JJ. Nutritional supplements for the treatment and prevention of sports-related concussion-evidence still lacking. Curr Sports Med Rep. 2017;16(4):247-255.
15. Cole JT, Mitala CM, Kundu S, et al. Dietary branched chain amino acids ameliorate injury-induced cognitive impairment. Proc Natl Acad Sci U S A. 2010;107(1):366-371.
16. Aquilani R, Iadarola P, Contardi A, et al. Branched-chain amino acids enhance the cognitive recovery of patients with severe traumatic brain injury. Arch Phys Med Rehabil. 2005;86(9):1729-1735.
17. Sharma B, Lawrence DW, Hutchison MG. Branched chain amino acids (BCAAs) and traumatic brain injury: a systematic review. J Head Trauma Rehabil. 2018;33(1):33-45.
18. Aquilani R, Boselli M, Boschi F, et al. Branched-chain amino acids may improve recovery from a vegetative or minimally conscious state in patients with traumatic brain injury: a pilot study. Arch Phys Med Rehabil. 2008;89(9):1642-1647.
19. Ashbaugh A, McGrew C. The role of nutritional supplements in sports concussion treatment. Curr Sports Med Rep. 2016;15(1):16-19.
20. Rich NJ, Van Landingham JW, Figueiroa S, Seth R, Corniola RS, Levenson CW. Chronic caloric restriction reduces tissue damage and improves spatial memory in a rat model of traumatic brain injury. J Neurosci Res. 2010;88(13):2933-2939.
21. Davis LM, Pauly JR, Readnower RD, Rho JM, Sullivan PG. Fasting is neuroprotective following traumatic brain injury. J Neurosci Res. 2008;86(8):1812-1822.
22. Liu Y, Wang R, Zhao Z, et al. Short-term caloric restriction exerts neuroprotective effects following mild traumatic brain injury by promoting autophagy and inhibiting astrocyte activation. Behav Brain Res. 2017;331:135-142.
23. Denniss RJ, Barker LA, Day CJ. Improvement in cognition following double-blind randomized micronutrient interventions in the general population. Front Behav Neurosci. 2019;13:115.