Protein Quality Not Excellent and Essential Fatty Acid Deficiency in Evacuation Shelter Food Analysis in the Noto Peninsula Earthquake: Comparison with the 2024 Simultaneous National Survey in Japan

1. Introduction

On January 1, 2024, a major earthquake measuring 7.6 magnitude struck the Noto Peninsula, located on the bay coast in north-central Japan, a country known for its frequent earthquakes. The next day, the non-profit organization Tokushukai Medical Assistant Team (TMAT) entered the disaster area in Wajima City to provide relief. After completion of registration as the Disaster Medical Assistance Team (DMAT), TMAT set up a makeshift clinic in an evacuation center and began executing the subsequent tasks. This article reported that 65% of the evacuees were elderly people aged 65 and over, who are vulnerable to disasters. It also reported that the food provided in evacuation centers was insufficient in energy and protein for older men and women, putting them at risk of protein-energy malnutrition (PEM) and PEM-related diseases such as infection, dehydration and acute kidney injury. An overview of the evacuee shelters provided in Noto Peninsula Earthquake (NPE) and the overview of food provided in the shelters have been reported elsewhere [1].

2. Materials and Methods

In the present study, we examined the adequacy of the contents of the meals provided in the evacuation shelters from aspects of the composition of amino acids and fatty acids. We also compared the results with those with results of a national survey of meal supplies for disasters in hospitals and welfare facilities that was planned in 2023 and conducted in January, 2024.

Methods: The amino acid and fatty acid composition of 11 evacuation meals provided to evacuation shelters in Wajima City, the city most affected by the NPE, was calculated from photographs taken during medical activities by TMAT. This method has been validated [2,3]. First, the amino acid and fatty acid analysis values were calculated independently by two registered dietitians. Second, the results were compared with the digestible essential amino acid score (DIAAS), which is used to assess the protein quality of the 11 types of meal provided, and the daily intake of essential amino acids was calculated and compared with the World Health Organisation (WHO) daily intake [4]. Similarly to amino acid analysis, the fatty acid composition was also compared with the daily intake of essential fatty acids recommended by European Food Safety Authority (EFSA) to verify validity [5]. Third, to know the quality and quantity of disaster-prepared food in hospitals and welfare facilities in Japan, the results of a nationwide survey of food stockpiled in hospitals and welfare facilities, planned for 2023 and conducted in January 2024, will be summarized and the obtained results will be compared with appropriate essential amino acid and essential fatty acid profiles.

Nutrient Composition Database for Foods

For calculation of the amounts of amino acids and fatty acids in the meals, foods were classified into food groups. All nutrients contained in each food group were calculated using the Standard Tables of Food Composition in Japan (8^th Edition, 2024) [6]. Then, the content of all amino acids and fatty acids was calculated. In this step, when there were missing values, a method was used to fill in the missing values with similar foods to avoid underestimating the values calculated by excluding the missing values.

“Duplicated Combination” Model to analyze all possible combinations of 3 meals selected from 11 different meals

Considering that disaster victims can freely choose 3 meals from 11 types of stockpiled meals allowing overlapping in their choice, we applied the orthodox mathematical model of “Duplicated Combination” model [7] using programming language. It is worth noting that this method has the potential for extension to a theoretically unlimited number of meals in shelters. This novel method could be available in time for the disaster shelters to provide detailed information not only on macronutrients, but also on amino acids and fatty acids individually appropriate for each victim, varying by age, sex and co-morbidities. The details of programming commands of this method are shown in the supplementary files. The details of this novel method are written in the supplementary files of “Duplicated combination”.

Calculation of The Digestible Indispensable Amino Acid Score (DIAAS)

DIAAS is an index recently recommended by the FAO as the most reliable way of assessing protein quality [8]. The formula for calculating DIAAS is as follows:

DIAAS (%) =100 X [(mg of digestible dietary indispensable or essential amino acid in 1 g of the dietary protein) / (mg of the reference of same dietary essential amino acid in 1 g of the reference protein)]

Here, the reference values of the essential amino acids in the denominator of the above equation for older adults are as follows: histidine 16, isoleucine 30, leucine 61, sulfur-containing amino acids (methionine and cysteine) 23, lysine 48, aromatic amino acids (phenylalanine and tyrosine) 41, threonine 25, tryptophan 6.6, and valine 40. All are expressed in the unit of mg/g of protein.

3. Results

Three meal types were selected from the 11 meal types actually provided in NPE shelters, and overlapping combinations were allowed, resulting in 286 types. For each of these 286 dietary combinations, the daily intake of amino acids and fatty acids was calculated.

Daily Amino Acid Intakes for sum of daily provided three Meals

The daily intake of essential and non-essential amino acids are shown (Table 1 and Table 2). The results of an analysis of the sufficiency rate of essential amino acids by gender, which is the ratio of the amount provided to the daily requirement of essential amino acids by gender as specified by WHO, are shown (Table 3).

This result is interpreted to mean that the amount of essential amino acids available in the shelters exceeds 100% of all essential amino acids, suggesting that there is no risk of essential amino acid deficiency in the shelters.

Half-life of Ingested Protein for Disaster Victims Is Determined by N-terminal Amino Acid

Assessing the nutritional value of foods provided in evacuation shelters in disaster areas, particularly amino acids, it is important to consider the metabolic turnover rate in the body. The metabolic turnover rate of amino acids is generally determined by the N-terminal amino acid of a protein, known as the "N-end rule" [9,10,11] (Tabel 3. In particular, when comparing the half-lives of essential amino acids, the half-life of valine is 100 hours and attention must be paid to valine deficiency after more than 100 hours or 1 week in the shelters. In the 11 types of formula examined in this study, the ratio of the essential amino acids contained in the formula to the WHO recommended amount of valine is greater than 1.5 for both men and women. However, the half-life of proteins with valine at the N-terminus is 100 hours, or about 4 days. Therefore, when living in a shelter for more than a week, there is a risk of developing essential valine deficiency, and attention must be paid to valine deficiency among the essential amino acids in the food provided. Conversely, in the case of deficiency of ECHS1, a key enzyme in the valine catabolic pathway, attention must also be paid to excess [12]. However, the Kapital paper did not examine special diets provided to patients with specific medical conditions, such as patients with maple syrup disease, a congenital metabolic disorder in which the patient is deficient in the enzymes that metabolize the branched-chain amino acids (BCAAs) valine, leucine and isoleucine.

Comparison of 11 Meals in essEntial Amino Acids Using DIAAS

The results of calculating the husband’s personal DIAAS by assigning letters from A to K to each of the 11 types of food provided in the evacuation shelter during the 21 days of TMAT activities at NPE are shown below (Table 4).

As a result, the DIAAS of the 11 diets ranged from a maximum of 0.92 to a minimum of 0.6. Of these, none of the meals reached 1.00The DIAAS cut-off is set at 100 or more / 75-99 as excellent / good [5]. As the aim of the present study was to prevent malnutrition in older adults who need more leucine to prevent age-related muscle loss, we set the DIAAS cutoff value at 1.00 [13], whereas 9 out of11 meals are considered good proteins if the cut-off value is set at 0.75. For these reasons, our result means that all 11 meals did not provide good dietary quality in terms of DIAAS.

Daily Fatty Acid Intakes for 3 Meals

The mean daily intakes of the 49 fatty acids analyzed in 11 meals are shown (Table 5). The daily intakes of linoleic acid and alpha-linolenic acid as the essential fatty acids, and sum of eicosapentaenoic acid and docosahexaenoic acid were calculated. They were tehn compared with the EFSA daily requirement recommendations and expressed in % (Table 6). In other words, neither was found to meet the medical daily requiremalet. Furthermore, when the sum of EPA and DHA was calculated as a compliance rate, it was found to be more than 300%, meaning that the requiremalet was met. The LA and ALA intakes were less than 40% of the EFSA recommendations. These results show that LA and ALA are deficient in three of the 11 foods in the shelter meals and need to be increased to meet the EFSA recommendations.

4. Discussion

Essential Amino acids and DIAAS in Shelter meals

On 21 September 2024, more than nine months after the NPE disaster, a Linear Precipitation hit the area exactly corresponding to the NPE, and secondary flooding also hit the NPE evacuation centers. This shows that living in an evacuation shelter for a long period of time and the meals provided in the evacuation shelter can trigger the onset of disaster-related comorbidities such as malnutrition and sarcopenia especially in the elderly as being vulnerable to disasters. To prevent and treat sarcopenia, the importance of leucine, among the essential amino acids that are the subject of protein quality assessment by DIAAS, has been reported [14,15,16,17]. Here, the average daily leucine intake of freely chosen three meals combination from 11 different meal types provided in the shelter was 3.4g, which was higher than the recommended daily intake of 3g. However, when focusing on each daily leucine intake in all possible 286 meal-combinations, 65 combinations contained less than 3 g of leucine and were at risk of developing sarcopenia [18,19,20]. In other words, it was found that caution should be exercised with meal combinations in terms of 3g of leucine.

Additionally, in recent years, it has been claimed that DIAAS indicates whether the protein is of animal or plant origin, which has traditionally been considered a simple alternative indicator of the amount of EAA. Reports on the effectiveness of sarcopenia treatment suggest that 3-hydroxy-3-methylbutyrate (HMB) [21,22], a metabolic product of leucine, may increase muscle mass, inhibit muscle loss, repair muscle and improve endurance by inhibiting protein catabolism or breakdown. The recommended dose of leucine is 3g/day and a maximum of 5-10% is converted to HMB. This means that a total of 30-60g of leucine is required [21]. As this daily intake of leucine carries a risk of adverse events such as azotemia leading to acute kidney injury (AKI), even when DIAAS is high and the protein is of good quality, the provision of HBM itself as a supplement in shelters may need to be considered. In summary, from the perspective of the EAA, our results suggest that supplementation with proteins high in DIAAS, but as leucine is insufficient even when DIAAS is high, HMB supplements may also be considered in shelter meals.

Finally, if a prolonged stay in shelters is expected, it seems important that measurement of muscle mass and strength and review of serum aminogram profiles should be considered for older adults staying in shelters for long periods after a disaster [23].

Fatty Acids Composition in Shelter Meals

The intake of polyunsaturated fatty acids (PUFAs) is also suggested to influence sarcopenia progression. However, although no data on n-3 PUFAs intake in sarcopenic older adults were published, sarcopenic older adults tend to take less n-3 PUFAs compared to them of non-sarcopenic people, and vice versa [24,25,26]. Our analysis of the essential fatty acids in the meals provided in the evacuation shelters revealed inadequate levels of linoleic acid (LA) and alpha-linolenic acid (ALA) (Figure 3), This suggests that there is a risk of essential fatty acid deficiency during long-term living in a shelter.

Second Disaster Hitting the Exact Same Area is Real

On September 23, 2024, nine months after the NPE, a linear precipitation band struck the exact same area as the NPE, causing flooding due to heavy rainfall that hit evacuation centers. This second disaster hitting and prolonged shelter stay may be a direct cause of sarcopenia in vulnerable disaster victims, similar to our experience with the Great East Japan Earthquake 13 years ago [27], leading to the occurrence of disaster-related comorbidities. Fatty acid analysis of the diet consumed in shelters is essential to prevent malnutrition due to n-3 fatty acid deficiency. To prevent essential fatty acid deficiency, 2g of n-3 fatty acids per day is recommended [20]. It is also recommended to consume fresh fruit, vegetables and fats or take appropriate supplements to maintain an optimal health-related quality of life [28,29]. In order to fully achieve these complex objectives, it is proposed that the disaster relief team be accompanied by nutrition experts trained in scientific observation and analysis, including knowledge of nutritional supplements.

From Results of National survey of Disaster-Preparedness meals

Background: Japan is one of the most earthquake-prone countries in the world, with 221 earthquakes of magnitude 6.0 or greater recorded in the 125 years since 1901 (Figure), involving the Great Kanto Earthquake GKE), the Great East Japan Earthquake (GEJE) and NPE, occurred on Sep. 1, 1923 (magnitude (Mg) 8.2), Mar 11,2011 (Mg 9.0) and Jan 1,2024 (Mg 7.6), respectively. Evaluation of the quality of evacuation meals provided by hospitals and welfare facilities providing relief in disaster-stricken areas is important for reducing the incidence of disaster-related comorbidities. Objects: To assess the nutritional quality and quantity of disaster prepared meals in hospitals and welfare institutions, which play a key role in disaster areas. Methods: Among government-certified Disaster Key Hospital 776 hospitals and almost 8000 Welfare facilities for disable or older adults, randomly 200 each were selected. As this survey was conducted immediately after the NPE, the disaster-affected prefectures of Ishikawa, Toyama and Niigata were excluded from the survey in order to prioritize disaster relief. A questionnaire on the quantity and quality of disaster preparedness meals was sent by post. This survey was approved by the Ethic committee of the studied university on Dec. 1, 2023. The approval number is 2023-001. Results 1 of Hospitals Survey: The response rate was 108 out of 198 hospitals (54.5%) as disaster base hospitals and the hospital size was 59 hospitals (55%) with 400 beds and 30 hospitals (28%) with 200 beds or more. 94 hospitals (87%) had a 3-day supply. The reason for this is unclear. The median (25%, 75%) stockpile per person was 1,956 ml (1041, 3315) water, 1,400 kcal (1126, 1500) protein 40.0g (30.0, 50.0) and salt 6.0g (4.0, 7.9). Results 2 of Welfare institutions Survey: The response rate was 122 hospitals (64.6%) out of 186, 95 (78%) nursing homes and 26 (21%) homes for the disabled. The number of days of storage was 3 days for 95 (78%), the median number of meals stored was 864 (576, 1080) and the number of meals per resident was 10 (9.00, 13.85). The median (25%, 75%) amount stockpiled per person was 480 ml (252, 860) of water, 1200 kcal (909, 1439) of energy, 36.8 g (30.0, 48.4) of protein, and 6.0 g (4.7, 8.0) of salt. Summary of National Survey: There were energy and protein deficiencies per person in both hospitals and welfare institutions. It was found that the food provided in evacuation shelters over a long period of time poses a high risk of developing protein-energy malnutrition.

Proposal of Protocol for A Nationwide Re-Survey of Amino acids and Fatty acids Using “Duplicated Combination” Model

We propose two novel protocols to assess the nutritional adequacy of stockpiled foods in two ways. First, we propose a novel method to calculate nutrients involved in meals in evacuation shelters in disaster. This is a method that can be used to quickly calculate the nutritional content of the wide variety of meals served in disaster area, and select the appropriate meals to serve. This method was applied to the amino acids and fatty acids contained in each meal for the disaster stockpile meals from hospitals surveyed national, and the excesses and deficiencies for each age and sex were calculated using the "Dietary Reference Intakes for Japanese" (2025 version) [30], which the Ministry of Health, Labour and Welfare plans to formulate and introduce for use in April 2025, as a reference to be used in determining appropriate emergency food supplies. Second, we are using the same survey facility to send us all the photographs of the stored foods prepared in the same way as the NPE, using the double combination method to assess the appropriateness of the amino acid and fatty acid composition. This will enable us to identify any inappropriate stored foods and improve the nutritional quality of the stored foods.These proposals are, to our knowledge, the first national survey to assess the quality of disaster-prepared food.

Strength and Limitations

The strength of this study is that it was the first to conduct a nutritional evaluation of NPE disaster preparedness foods from the perspective of amino acid and fatty acid composition. A previous analysis of the energy and protein content of NPE pre-prepared foods showed that they were inadequate for the elderly. However, this amino acid analysis used the DIAAS, currently the most reliable indicator for assessing protein, and the results showed that the DIAAS of all 11 types of prepared meals analyses did not reach 1.00, highlighting the need to improve the protein quality of preparedness foods in the next stage. Other than DIAAS used this time, other indicators used to assess protein quality include Amino Acid Score, Biological Value (BV) [31], Net Protein Utilisation (NPU) [32], Protein Efficiency Ratio (PER) [33] and Protein Digestibility Corrected Amino Acid Score (PDIAAS), which adds digestibility to the amino acid score. Comparing DIAAS with PDIAAS, the PDCAAS uses fecal digestibility and is truncated at 100%, while the DIAAS uses ileal digestibility but is not truncated at 100% and, more importantly clinically, the DIAAS provides values for three different age groups with more recent data on human requirements. From these reasons, DIAAS is currently the most accurate score [34]. In a disaster evacuation environment, this method appears to be ideal for assessing elderly people whose digestive function may be compromised. The limitations of this study must also be mentioned. First, no evidence was found that older people who consumed these stored foods over a long period of time developed iron-related health problems, such as essential amino acid deficiency, sarcopenia, frailty, or essential fatty acid deficiency. This is an issue that needs to be addressed in the future. Second, DIAAS cut-off values specific to older people are 100 for excellent quality and 75 for good quality, which are set by FAO for the general adult population, but is 100 really appropriate or should a DIAAS cut-off value be set specifically for older people? Further detailed consideration is needed. Third, in disaster areas where electricity is not available, it may not be possible to use the proposed double combination model with statistical software on computers in disaster environments. Therefore, it is necessary to follow the protocol foreseen in the proposal and to perform amino acid and fatty acid analysis of the disaster meals as soon as possible. Fourth, the missing values of amino acids in the food composition tables are replaced by alternative foods using the substitution method, so there is a good chance that errors have occurred. In general, the tolerance limits proposed by CODEX are limited to 20% [35,36]. However, as the amino acid content varies from food to food, we have to take into account that there are no absolute values for amino acid contents.

5. Conclusions

Analysis of meals in evacuation shelters after the Noto Peninsula Earthquake revealed two problems. First, the daily intake of essential amino acids was adequate, but DIAAS available as an indicator of protein quality was low. In addition, daily intakes of n-3 fatty acids were also inadequate. Second, a nationwide survey of disaster food stocks in disaster relief hospitals and welfare facilities found that they were deficient in protein and energy, and that there was a risk of protein-energy malnutrition for older adults who are vulnerable in the post-disaster environment. The next step in the national survey will be to conduct a nutritional analysis of the emergency food stocks in terms of amino acid and fatty acid analysis.