5 silent signs your body may be missing key nutrients, according to a neurologist

A busy lifestyle makes it easy to dismiss unusual changes in the body. A little fatigue is blamed on work. Forgetfulness is brushed aside as ageing. Tingling sensations are ignored as temporary discomfort. But, in many cases, these seemingly ordinary experiences may point to something deeper: a deficiency of essential nutrients.

Nutrition is not only about maintaining body weight or building muscles. Every cell in the body relies on vitamins, minerals, proteins, and healthy fats to perform its functions. When these nutrients are lacking, the body begins to send signals. The challenge is that these signals are often subtle and can easily be mistaken for everyday stress.

According to the Indian Council of Medical Research (ICMR) and the National Institute of Nutrition (NIN), micronutrient deficiencies continue to be a public health concern in India, affecting people across age groups.

The body often reveals nutritional imbalances long before laboratory reports confirm them.

Many people assume exhaustion is an unavoidable consequence of modern life. However, persistent fatigue that does not improve with rest may signal a nutrient deficiency.

TOI spoke to Dr Pradyumna Oak, Principal Director, Neurology, Centre of Neurosciences, Nanavati Max Hospital, Mumbai, who explained, "A lack of vitamin B1, also called thiamine, can affect the way the brain uses energy. Early deficiency may show up as fatigue, low mood, poor appetite, abdominal discomfort, mental dullness or nerve-related symptoms."

The brain consumes nearly 20 percent of the body's energy despite accounting for only a small fraction of body weight. When nutrients involved in energy production are insufficient, mental and physical performance can suffer.

Iron deficiency can produce similar effects. The body requires iron to carry oxygen to tissues and organs. Without adequate iron, even simple activities may feel exhausting.

"Low iron can be associated with apathy, depression and rapid fatigue during activity. In children, iron deficiency has been linked with attention and cognitive difficulties. In adults, it can add to a sense of reduced stamina and poor concentration," said Dr Oak.

Many people spend months searching for productivity hacks when the real issue may be a nutrient imbalance that deserves medical attention.

A tingling sensation in the feet, burning pain, numbness, or the feeling of walking on a soft cushion may seem harmless at first. Yet these symptoms can indicate that the nervous system is under strain.

"The brain is considered the core differentiator between humans and all the other species. It is the epicentre of thoughts, memory and emotions and also one of the most nutrition-dependent organs in the body," said Dr Oak.

One of the most common nutrient-related causes of nerve problems is vitamin B12 deficiency.

"Vitamin B12 deficiency is an important cause to consider, particularly in older adults, vegetarians, vegans, people with stomach or intestinal absorption problems, and those who have undergone bariatric or gastric surgery," he explained.

What makes B12 deficiency particularly concerning is that nerve damage can begin before anaemia becomes obvious on routine blood tests.

Dr Oak noted, "B12 deficiency may cause memory issues, attention problems, mood changes, nerve pain, abnormal sensations in the hands and feet, imbalance and, in some cases, vision-related nerve problems."

Another lesser-known culprit is copper deficiency. While rare, inadequate copper levels can affect the spinal cord and nerves, leading to walking difficulties, weakness, stiffness, and sensory disturbances.

The conversation around nutrition often focuses on physical health. However, nutrients are equally important for emotional and cognitive well-being.

Many vitamins play a direct role in producing neurotransmitters, the chemical messengers that regulate mood, attention, sleep, and memory.

Dr Oak explained, "Deficiency of niacin, or vitamin B3, can affect the nervous system and may present with headache, insomnia, depression, memory problems, confusion and, in severe cases, hallucinations or coma."

Vitamin B6 also supports the production of brain chemicals involved in emotional regulation.

Similarly, folate is essential for memory and healthy brain function, particularly during pregnancy and older age.

When nutrient levels decline, the brain often struggles quietly before symptoms become severe. A person may notice irritability, mental fog, poor concentration, reduced motivation, or disrupted sleep patterns without realising that nutrition may be contributing to the problem.

Research from the National Institutes of Health has repeatedly highlighted the relationship between micronutrient status and cognitive performance, particularly among older adults and growing children.

Sometimes, what appears to be burnout may actually be a body asking for nutritional support.

One nutrient that rarely receives enough attention is iodine.

Most people associate iodine with thyroid health, but its role extends far beyond the thyroid gland.

"Iodine, through thyroid hormone, supports brain development and brain cell energy. Long-standing thyroid-related iodine deficiency may be associated with cognitive delay, depression, dementia or seizures," said Dr Oak.

The World Health Organization considers iodine deficiency one of the most preventable causes of impaired cognitive development worldwide.

The connection between nutrition and brain health is often underestimated until symptoms begin affecting everyday life.

The wellness industry frequently promotes supplements as a quick solution to fatigue, poor memory, or low energy. However, experts warn that self-prescribing vitamins can sometimes do more harm than good.

"These symptoms do not prove a deficiency on their own. Many neurological and medical conditions can look similar," said Dr Oak.

He added, "If fatigue, memory decline, tingling, imbalance, poor attention, mood changes or vision symptoms persist, it is advisable to seek medical evaluation rather than self-prescribing supplements because at times, few nutrients like iron, vitamin A and zinc, can be harmful in excess."

This is particularly important because excessive supplementation can create new problems. For example, too much zinc can interfere with copper absorption, potentially leading to neurological symptoms.

The safest approach is not to chase trending supplements but to focus on a balanced and sustainable diet.

Dr Oak emphasised, "The brain does not need expensive or trending diets. It needs consistency: adequate protein, grains, pulses, vegetables, fruits, dairy or appropriate alternatives, nuts, seeds and sources of healthy fats."

When dietary restrictions, chronic illness, digestive disorders, or prolonged recovery from disease affect nutrient intake, targeted testing may help identify deficiencies before lasting damage occurs.

Nutrient deficiencies rarely arrive with dramatic warning signs. More often, they appear as everyday complaints that seem easy to overlook. Persistent fatigue, brain fog, tingling sensations, poor concentration, mood shifts, sleep disturbances, and memory lapses may all be clues worth paying attention to.

The body has an extraordinary way of communicating when something is missing. Recognising those signals early can make the difference between a simple correction and a long-term health problem.

Good nutrition is not about perfection. It is about giving the body and brain the consistent support they need to function at their best.

This article includes expert inputs shared with TOI Health by:

Dr Pradyumna Oak, Principal Director, Neurology, Centre of Neurosciences, Nanavati Max Hospital, Mumbai.

Inputs were used to explain the subtle signs and symptoms that may indicate deficiencies in essential nutrients, how these deficiencies can affect brain and nerve function, and why timely medical evaluation and a balanced diet are important for maintaining overall health.