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Multidimensional Approach to Assess Nutrition and Lifestyle in Breastfeeding Women during the First Month of Lactation

The first month of lactation is a vulnerable nutritional period for the mother. Our aims were (1) to evaluate the nutritional status of breastfeeding women in the first month of lactation, and (2) to explore different aspects of nutrition and lifestyle through a multidimensional approach. A total of 30 healthy breastfeeding women were enrolled in this study. Dietary pattern was assessed through a 72-hour dietary recall questionnaire (days 7 and 28 postpartum) and data were compared with Dietary Recommendation Values (DRV), and through the Adherence to Healthy Food Pyramid (HFP) questionnaire (day 28). Anthropometric parameters were evaluated by bioimpedance. Using factor analysis, nutritional dimensions were extracted, and linear regression models were used to analyze the association between anthropometric parameters and dimensions. Compared to the DRV, women showed insufficient energy, water, vitamin D, and potassium intake and excessive proteins, vitamins B1, B2, B3, B6, B12, and iron intake. We observed a moderate adherence to the HFP, with women being high in the fruits, vegetables, and oil categories, and low adherence to the physical activity, dairy products, and hydration categories. The nutritional dimension, including the HFP categories of physical activity, hydration, and animal protein intake together, was negatively associated with body weight (β = −3.7 ± 1.7; p-value = 0.047). In conclusion, during the first month postpartum, breastfeeding women exhibited several nutritional imbalances and poor physical activity negatively influencing anthropometric parameters. We propose a multidimensional approach to assess the nutritional status of breastfeeding women as a tool to detect specific deficiencies, allowing for personalized counseling.


Introduction
Maternal nutrition during pregnancy and lactation is critical for both mother and child's health. During breastfeeding, nutritional and metabolic demands are considerably higher in lactating women [1], due to the energy expenditure involved in breastmilk (BM) production [2]. Lactation is a nutritionally vulnerable period for the woman, and if insufficient or inadequate, such as in low-income settings, it has an enormous impact on maternal health [3]. However, in high-income countries, where women have access to a sufficient amount of food, the nutrition of breastfeeding women may not be necessarily adequate, it may be in excess or unbalanced, as part of the general health problem of obesity in western countries. Moreover, during breastfeeding, the woman is primarily focused on the newborn and thus neglects her own diet. Maternal diet affects BM composition; in Nutrients 2021, 13, 1766 2 of 14 particular, levels of vitamin A, D, B1, B2, B3, B6, and B12, fatty acids, and iodine depend on maternal diet [4]. Together with diet, maternal body composition and fat stores also influence BM compounds. Therefore, a healthy diet ensures not only a good maternal nutritional status, but also optimal concentrations of important BM components and the newborn's health.
Despite the importance of maternal nutrition during lactation, in some countries, such as Spain, there are no specific nutritional recommendations for this period, and guidelines for anthropometric parameters are based on pregnant women or the nonbreastfeeding adult population. This could be due to the lack of studies addressing women's nutritional status during the lactation period compared to those during pregnancy. There is also an ongoing debate about supplementation during lactation; for example, how much and for how long the supplementation should be provided. The need for nutritional supplements depends on many factors, including socioeconomic status, cultural differences, and unhealthy maternal habits. In low-income settings, supplementation has been demonstrated as an effective strategy to compensate for nutritional deficiencies [5]. In high-income countries, supplementation has been mostly focused on long-chain fatty acids (LCPUFAs). Studies have shown that omega-3 (n-3) LCPUFA supplementation results in an increased level of docosahexaenoic acid in BM [6] and it is associated with improved neonatal health outcomes [7]. In European countries, efforts have been made-through an international research consortium-to summarize current evidence in order to provide guidelines and regulations on nutrition and supplementation in lactating women [8]. Despite important conclusions, mainly focused on the aspect of maternal nutrition to reduce the infant's risk of overweight, this consortium has evidenced the need for additional studies to develop specific recommendations based on scientific evidence, which could lead to improved public health strategies [9][10][11]. Furthermore, an individualized approach to nutritional counseling considering women's nutritional status and body composition has been proposed [12].
The Healthy Food Pyramid (HFP) is a simplified graphic representation of the main characteristics of the Mediterranean Diet. It is the main framework for the different sociocultural contexts of the Mediterranean region and aims to promote adherence to this healthy dietary pattern [13,14]. The benefits of this dietary pattern are well established [15,16]. A systematic review has confirmed that the Mediterranean Diet in lactating women decreases the risk of allergic disease and thus is beneficial for the newborn [17]. However, a gradual loss of this healthy food pattern was observed during pregnancy and the postpartum period [18]. In addition to the nutritional dimension, the HFP also takes into account other dimensions that include lifestyle or physical activity. Our research group has developed a questionnaire of adherence to the HFP (AP-Q) that analyzes these dimensions in addition to the nutritional condition, and thus provide a robust tool enabling one to assess several features that can affect overall maternal health status [19].
Breastfeeding is a vulnerable period for lactating women, particularly if the mother does not receive adequate nutritional recommendations. Our principal aim was to gain insight into the nutritional status of breastfeeding women in Spain during the first month of lactation. The objectives of the present study were to investigate whether the maternal nutritional pattern followed the dietary recommendations during the first month of lactation; their degree of adherence to the HFP, the dimensions that needed to be improved, and the association between nutritional and anthropometric variables. The knowledge gained by this study, using a multidimensional approach based on different dietary and lifestyle components, could help health professionals to design individualized interventions for breastfeeding women, based on the detected deficiencies.

Population of Study
Mothers were enrolled within the first 72 h postpartum at the Obstetrics and Gynecology and Neonatology Departments of the Hospital Clínico San Carlos (HCSC, Madrid;

Measurement of Maternal Dietary Patterns
Maternal dietary patterns were studied using two complementary surveys, (1) the 72-h dietary recall (72hDR) method and (2) the Adherence to Healthy Food Pyramid questionnaire (AP-Q).
Adherence to Healthy Food Pyramid questionnaire (AP-Q). This is a self-administered questionnaire developed and validated in the general population [19] that estimates the adherence to the HFP, which is a healthy standard for countries in the Mediterranean area [13,14]. It measures the frequency of consuming food of different categories during the last month. Mothers answered the AP-Q at 28 ± 1 days postpartum. The AP-Q consisted of 27 questions with multiple responses. The responses given to each item were grouped into ten different categories, including physical activity, healthy habits and culinary techniques, hydration, grains, seed and legumes, fruits, vegetables, oil type, dairy products, animal proteins, and snacks. Each category was scored on a scale of 0 to 1; the higher the score, the greater the adherence to the HFP. In HFP, the food categories at the bottom of the pyramid represent healthy habits (physical activity, culinary techniques, hydration, grains, seed and legumes, fruit and vegetables) and have positive scores, while categories at the top (snacks or foods that are not included in HFP) have negative scores.

Measurement of Maternal Anthropometric Parameters
Maternal anthropometric parameters were measured at days 7 ± 1 and 28 ± 1 postpartum. Height (cm) was quantified by stadiometer (Seca 217, TAQ sistemas medicos, Madrid, Spain), and waist and hip circumferences (cm) were measured using anthropometric tape with millimeter precision (Seca 201, TAQ sistemas medicos). The waist-to-hip ratio was also calculated. Body weight (kg), total fat and muscle mass (%), and basal metabolic rate (kcal/day) were estimated using a bioimpedance meter (Omron Healthcare HBF-514C Full Body Sensor W Scale, Madrid, Spain), according to the manufacturer's instructions. The body mass index (BMI; kg/m 2 ) was also calculated.

Statistical Analysis
The Shapiro-Wilk test was used to examine the distribution of the variables and quantitative measurements were either expressed as mean ± standard error of the mean (SEM), for those with normal distribution, or as a median and interquartile range (Q1; Q3) for variables that did not follow a normal distribution. Qualitative variables were reported as a percentage (%) along with the sample size. To compare the maternal diet with the given dietary reference value (DRV), one-sample Student's t-test or Wilcoxon signed-rank test were performed. The statistical difference in diet between day 7 and 28 of lactation was analyzed by paired Student's t-test or Wilcoxon signed-rank test with continuity correction. The AP-Q categories between women with term and preterm delivery were analyzed using the Student's t-test.
Th sphericity of the dietary variables was evaluated by Barlett's test and Kaiser-Meyer-Oklin (KMO) score. For cluster analysis, KMO score ≥0.7 and a significant Barlett's test were considered adequate. Thereafter, the dimensions with eigenvalues ≥1 were extracted, according to Kaiser's rule. The grouping was carried out according to dimensions. The weight of each dietary dimension was calculated by the standardized loading of dietary variables within a given dimension. The standardized loading was extracted from the varimax-rotated matrix, considering a cut-off ≥0.45 to avoid overlapping in the dietary variables. Correlations were performed by the Rho-Spearman test and presented as a correlation matrix.
Linear regression models were used to study the association between anthropometric parameters and dietary dimensions after adjusting for maternal age (continuous), gestational age (continuous), ethnicity (categorical), educational level (categorical), employment status (categorical), and supplementation (yes/no) during the lactation period. Estimated beta coefficient ± standard error was reported.
We did not detect statistical differences in any of the macro or micronutrients between day 7 and 28 postpartum (Table 1; p-value 2 ). Dietary Recommendation Values (DRV) according to the population reference intake of a nutrient that is likely to meet the needs of a healthy population or the average requirement refers to the intake of a nutrient that meets the daily needs of people in a healthy population [12,25,26] for breastfeeding population; as low as possible (ALAP). 1 Comparison with DRV (↓ = below DRV; ↑ = above DRV); 2 comparison between day 7 and 28 ( a Wilcoxon signed-rank test with continuity correction; b paired Student's t-test). Arrows indicate deviations from DRV.
To prove whether the maternal diet of the cohort was in accordance with recommendations during the first month of breastfeeding [12,25,26], we compared and analyzed maternal nutrient intake at day 7 and 28 with the recommended values. We found that maternal diet was significantly deficient in energy, water, vitamin D, and potassium at day 7 and 28 compared with the DRV. In contrast, the levels of protein, vitamins B1, B2, B3, B6, B12, and iron were significantly higher at both time points, compared to the DRV. Saturated fatty acids intake was high on days 7 and 28 since the recommended intake is "as low as possible" ( Table 1). The levels of vitamin A and B9 were significantly lower on day 7, while the levels of vitamin B7 and E were significantly higher on day 28 compared to the recommendations (Table 1; p-value 1 ).

Factor Analysis for Maternal Dietary Pattern
Cluster analysis was performed using all dietary variables on day 28. The suitability of this analysis was demonstrated by the significant sphericity (χ 2 = 2699.2; p-value < 0.001) and a KMO score of 0.93. Thereafter, Kaiser's rule was applied to extract the optimal number of dimensions. We found six dimensions with eigenvalues ≥ 1, which explained 67% of the variance. Dimension 1-6 accounted for 17.2%, 14.8%, 11.7%, 9.6%, 7.7%, and 5.9% of explained variance, respectively. The macronutrients were distributed in dimension 1. In dimension 2, most of the vitamins and the healthy habits category were found. In dimension 3, fiber, vitamin K, potassium, grain, and snacks categories were clustered. Dimension 4 included fruit, vegetables, dairy products, and oil categories. Dimension 5 included iodine and iron, and in dimension 6 physical activity, animal protein, and hydration categories clustered together (Table S3).

Maternal Anthropometric Parameters and Relationship with Maternal Dietary Pattern
Changes in maternal anthropometric parameters from day 7 to day 28 are shown in Table 2. From day 7 to day 28 of lactation, a significant decrease in maternal body weight, BMI, waist circumference, waist-to-hip ratio, muscle mass, and basal metabolic rate was detected. In contrast, a significant increase in fat mass was observed during this period.

Factor Analysis for Maternal Dietary Pattern
Cluster analysis was performed using all dietary variables on day 28. The suitability of this analysis was demonstrated by the significant sphericity (χ 2 = 2699.2; p-value < 0.001) and a KMO score of 0.93. Thereafter, Kaiser's rule was applied to extract the optimal number of dimensions. We found six dimensions with eigenvalues ≥ 1, which explained 67% of the variance. Dimension 1-6 accounted for 17.2%, 14.8%, 11.7%, 9.6%, 7.7%, and 5.9% of explained variance, respectively. The macronutrients were distributed in dimension 1. In dimension 2, most of the vitamins and the healthy habits category were found. In dimension 3, fiber, vitamin K, potassium, grain, and snacks categories were clustered. Dimension 4 included fruit, vegetables, dairy products, and oil categories. Dimension 5 included iodine and iron, and in dimension 6 physical activity, animal protein, and hydration categories clustered together (Table S3).

Maternal Anthropometric Parameters and Relationship with Maternal Dietary Pattern
Changes in maternal anthropometric parameters from day 7 to day 28 are shown in Table 2. From day 7 to day 28 of lactation, a significant decrease in maternal body weight, BMI, waist circumference, waist-to-hip ratio, muscle mass, and basal metabolic rate was detected. In contrast, a significant increase in fat mass was observed during this period. The correlations between anthropometric parameters and the dietary pattern dimensions are presented as a correlation matrix in Figure 2. As expected, a positive correlation was observed between the anthropometric variables, as well as between the different dimensions. water intake, fats, SFAs, MUFAs, PUFAs, cholesterol, carbohydrates, proteins, sodium, and calcium) was positively and significantly correlated with muscle mass (rho = 0.36; pvalue = 0.009), and it was negatively correlated with waist circumference (rho = −0.37; pvalue = 0 To assess whether there was an association between the anthropometric parameters and dimensions 1 and 6, linear regression models, adjusted for maternal age, gestational age, ethnic group, educational level, employment situation, and breastfeeding supplementation, were built (Table 3). We did not find a significant association between dimension 1 and any of the anthropometric parameters. Dimension 6 was negatively and significantly associated with body weight and was close to the significance level for waist circumference. Table 3. Linear regression models to study the association between maternal anthropometric parameters and dietary pattern correlated dimensions. Regarding the relationship between anthropometric parameters and dietary pattern dimensions, dimensions 1 and 6 showed significant correlations. Dimension 1 (energy, water intake, fats, SFAs, MUFAs, PUFAs, cholesterol, carbohydrates, proteins, sodium, and calcium) was positively and significantly correlated with muscle mass (rho = 0.36; p-value = 0.009), and it was negatively correlated with waist circumference (rho = −0.37; p-value = 0.008). Dimension 6 (physical activity, hydration, and animal protein of the AP-Q categories) was significantly and negatively correlated with body mass index (rho = −0.48; p-value = 0.002), fat mass (rho = −0.43; p-value = 0.004), weight (rho = −0.46; p-value = 0.002), and waist circumference (rho = −0.38; p-value = 0.006).
To assess whether there was an association between the anthropometric parameters and dimensions 1 and 6, linear regression models, adjusted for maternal age, gestational age, ethnic group, educational level, employment situation, and breastfeeding supplementation, were built (Table 3). We did not find a significant association between dimension 1 and any of the anthropometric parameters. Dimension 6 was negatively and significantly associated with body weight and was close to the significance level for waist circumference.

Discussion
In this study, we evaluated the nutritional status of breastfeeding women from different perspectives in order to explore different areas that may be susceptible to intervention. Here, we showed that the diet of the breastfeeding women in our cohort, with a middleupper socioeconomic status in Spain, is imbalanced in several nutrients. Moreover, women receive supplementation on a regular basis, which may not always be needed. Their dietary pattern showed a moderate adherence to the HFP, with the worse aspects being physical activity, hydration and dairy products. We also found that dimension 6 (which includes physical activity, hydration, and animal proteins) was negatively associated with maternal body weight and waist circumference, suggesting the impact of dimension 6 on maternal anthropometric parameters during the first month of lactation. We conclude that the proposed multidimensional approach evaluating different aspects of nutrition and lifestyle, could help to identify specific deficiencies in breastfeeding women, allowing for personalized counseling during this important period of life. Our data also evidence the importance of addressing the normal range for maternal anthropometric parameters during the first month of lactation in larger cohorts. These data will be valuable for personalized counseling during this important period of life.

Breastfeeding Women's Diet Show Nutritional Differences for Dietary Recommendation Values
Our results showed that during the first month postpartum, breastfeeding women were deficient in energy, water intake, vitamin D, and potassium compared with the recommendations for the breastfeeding period. On the other hand, the intake of proteins, saturated fatty acids, vitamin B complex and iron were above the recommended levels. For calorie consumption, our study population was below the recommendations, specifically on day 28 (1870 kcal/day). It has been demonstrated that calorie intake less than 1800 kcal/day results in decreased milk production and macronutrient concentration in BM, which may be clinically relevant [27].
Several studies have shown that the Spanish population tends to reduce energy intake and the quality of the diet is gradually deteriorating, moving away from the Mediterranean Diet. Our data showed that the intake of protein and saturated fatty acids exceeded recommendations, which could lead to a decreased carbohydrate consumption, as previously described in adult population [28,29]. A high intake of saturated fatty acids might result in increased cholesterol levels that might have negative consequences for maternal health [30]. However, we found an adequate intake of polyunsaturated fatty acids. We did not detect whether there was an adequate consumption of the different n-3 and n-6 LCPUFAs, since DRV only includes linoleic, linolenic acids, and the combination of eicosapentaenoic and docosahexaenoic acids. It would be important to have reference values for all n-3 and n-6 LCPUFAs to achieve an adequate intake. Knowledge of the DRV of these important fatty acids during the breastfeeding period could be used for counseling, since the Western diet is usually misbalanced, with an increased n-6 and decreased n-3 intake, which plays an important role in obesity [31]. Besides, maternal supplementation with n-3 LCPUFAs results in increased levels of docosahexaenoic acid in BM [6], which is associated with improved neonatal health outcomes [7].
We found a low water intake in our study population, which could be due to failure to recall it in the 72hDR questionnaire. However, the data of the AP-Q-hydration category confirmed the low water intake, suggesting that the importance of hydration was neglected in breastfeeding women and needs to be improved through counseling. Besides, the similarity between the information provided by both questionnaires supports the utility of the AP-Q. Our data are in accordance with a previous report, showing insufficient total water intake in breastfeeding women, which also evidenced that water in food was the principal source [32]. There is no clear evidence showing the impact of the amount of water intake in breastfeeding women on BM production [33]. A lack of well-conducted trials and the impact of hydration on BM production deserves further attention [34].
Regarding vitamin intake, our data demonstrated that the consumption of watersoluble vitamins is above the recommended levels. This may be related to the fact that the vast majority of the mothers had a high intake of fruits and vegetables, with good adherence to the HFP, and they were also taking supplements. Since there is a relationship between maternal consumption of water-soluble vitamins and their content in BM [35], it is possible that the level of these vitamins may be adequate for BM. On the other hand, the vitamin A, vitamin D, and folic acid, were below the recommended levels. Vitamin A was low at day 7 but improved by day 28, suggesting that they probably had a diet deficient in vitamin A during gestation (at least by the end of gestation). In western countries, vitamin A supplements are not suggested for pregnant women who consume the recommended dietary allowance during their reproductive years. Studies have suggested that increased consumption of vitamin A-rich foods can meet increased demands during the lactation period [36]. Our data suggest that it would be important to detect women with diets deficient in Vitamin A to provide an appropriate recommendation. Vitamin D in our population was far below the recommended values. Besides, 24% of the cohort had a vitamin D deficiency clinically determined in pregnancy, which could be related to an inadequate consumption of food containing Vitamin D as well as a low sun exposure [37]. Dairy products provide a natural food source for Vitamin D, in many cases such as cow's milk, because they are often fortified with this vitamin. The 72hDR data showed that vitamin D intake is in accordance with previous reports, suggesting significantly decreased Vitamin D in recent decades [38]. Vitamin D is transferred from maternal serum to BM [39,40] suggesting that infants of mothers who consume less Vitamin D could also be deficient. Therefore, dietary counseling is clearly needed in breastfeeding women. During pregnancy, supplementation is usually provided to women with deficiency. Our study indicates that, if the diet is poor in Vitamin D, it may be beneficial to continue supplementation during the breastfeeding period. This would benefit both the mother and the infant since it has been demonstrated that maternal supplementation, as well as exposure to the sun, increases vitamin D in breastmilk [41].
Our data also showed insufficient levels of folic acid in maternal diet at the beginning of the breastfeeding period, but at day 28 these levels were within the recommended values. These results could be possibly due to the discontinuation of prenatal folic acid supplements after childbirth [42] followed by a diet improvement afterward during the lactation period. However, given our results, it may be useful to recommend maintaining folic acid supplementation during the first month of lactation if the maternal diet does not provide sufficient amounts. Substantial variations in folate recommendations for lactating women are found across countries (260-650 µg/day) [43]. These measurements are based on BM folate levels. We suggest that it would be more appropriate to detect maternal diet deficiencies through nutritional questionnaires, in order to give nutritional counseling or provide supplementation to women if needed.
In our study population, vitamin E levels were high on day 28. Vitamin E is particularly important at the early stages of life, as it acts as a defense against oxygen-induced toxicity in the extrauterine environment. BM is responsible for supplying the demand of vitamin E to the neonates [44]. Vitamin E is present in vegetables, oils, nuts, and seeds, and the adequate intake in our population is likely related to the consumption of these food categories, evidenced through the AP-Q.
Regarding minerals, calcium, iodine, and sodium levels were adjusted to the recommendations throughout the first month of lactation. Although daily calcium intake is well below the recommended levels in many countries, particularly in low-income settings [45], our cohort showed adequate levels, which may be related to the supplementation. Calcium supplementation during breastfeeding has some controversies. On one hand, it has been proposed that it may damage iron status, although this has been refuted by studies demonstrating that long-term calcium supplementation did not impair iron stores in breastfeeding women [45,46]. On the other hand, there is a paradox with calcium supplementation in pregnant women with a calcium-poor diet, and it has been reported that it may harm the woman's skeletal system [47]. We suggest that it would be wise to have specific information on the nutritional status of each mother to detect those who can benefit from supplementation.
Potassium intake was below the recommended values. Potassium levels may influence the physiological parameters of the mother, such as blood pressure. In fact, a diet rich in potassium has been shown to have blood pressure-lowering effects [48]. The major sources of potassium are lentils, red beans, nuts, dairy products, meat, poultry, and fish [49]. Considering the important role of potassium and its balance with sodium, increased intake of dairy products and cereals would be beneficial for breastfeeding women.
In our study population, iron intake exceeds (up to 90 mg) the recommendations. This exceeding level of iron could be due to the iron supplementation during breastfeeding. However, excessive iron intake may result in increased oxidative stress and impaired glucose metabolism [50], suggesting that it would be important to reduce these doses or even eliminate them if there is no iron deficiency.

Anthropometric Parameters
During pregnancy, the maternal body undergoes several metabolic adaptations, such as increased fat mass, as a reserve of energy stores to supply the increased energy demand for the developing fetus, and for mammary gland growth to ensure and maintain lactation [1,51]. Therefore, pregnancy and postpartum are periods of increased vulnerability for the retention of excess body fat. In industrialized societies, being overweight in the perinatal period is a relevant problem and has a negative impact on maternal and neonatal health. Overweight and obese women initiate breastfeeding later and have a shorter duration [52], and obesity negatively affects BM composition [53].There is evidence that lactation promotes maternal weight loss through the mobilization of the fat deposits accumulated during pregnancy [54]. It has been shown that women who breastfed for more than 6 months had less central adiposity and reduced body weight retention [55] later on compared to those who did not breastfeed [56]. A systematic review showed that this effect is markedly dependent on the time points measured and breastfeeding intensity, being mostly observed with prolonged periods of lactation [54]. Few studies have focused on the body composition changes during the first month of lactation to establish the average anthropometric values during early postpartum. Our data show that during the first month, women reduce their body weight and BMI. However, according to the bioimpedance data, weight loss was related to lean mass reduction, while fat mass was increased. Our data are in accordance with a recent study in Mexico, showing reduced BMI together with a lean mass between the 8-16th week postpartum [57]. Although BMI has been taken as the gold standard for fat mass, increasing evidence indicates that it may not always be a good parameter to predict obesity, at least in some populations [58][59][60]. In accordance with these reports, our data also suggest that BMI might not be a good indicator of overweight or obesity in breastfeeding women, at least in the early stages of lactation. These results suggest that other tools are needed to distinguish cases with normal BMI but with high-fat mass, such as waist-to-hip ratio or fat mass measured by other methods such as bioimpedance or DEXA. To the best of our knowledge, there are no specific anthropometric reference values for breastfeeding women at different states of lactation. We suggest that it would be important to obtain such values through large cohort studies.
We also evaluated the relationship between anthropometric parameters and dietary pattern dimensions, which could help to provide specific counseling to women to improve their anthropometry and health outcomes. Our cluster analysis was performed using all dietary variables on day 28. It resulted in six dimensions, which explained the 67% of the variance. Dimensions 1 and 6 were significantly correlated with the anthropometric parameters. Furthermore, dimension 6 (physical activity, hydration, and animal protein) exhibited a negative association with body weight and waist circumference. These data suggest that improved physical activity, hydration, and high intake of high-quality animal proteins could have a beneficial impact on maternal anthropometry, such as reducing body weight and waist circumference. The relevance of physical activity was also evidenced by the AP-Q, which showed a low adherence in our population. This is likely related to the fact that in the first month postpartum, the mother needs to recover from delivery, and she is more focused on the infant's health than her own. However, although we did not detect differences in the AP-Q between mothers with and without preterm delivery, it should be noted that mothers with premature infants, who are usually hospitalized during the first month of life, could skew feeding and adherence to the HFP. Around 60% of the population studied had other children, which could modulate their dietary and life-style pattern. This aspect was not explored in the present study, but deserves further analysis, comparing women who have their first child and those with previous lactation experience. Physical inactivity during the breastfeeding stage would likely lead to a loss of lean mass. This could also be related to insufficient energy consumption, as shown in our cohort. Although we detected an excessive consumption of proteins during the first month, this consumption may be of low quality. Furthermore, they can have excess saturated fats, which may result in an increased fat mass during the first month of lactation. Our data suggest that it would be important to provide specific recommendations to the mothers on the consumption of high-quality proteins, such as those present in oily fish, which also would improve the ratio n-3:n-6.

Conclusions
This work focuses on breastfeeding women, a population that may be nutritionally vulnerable, particularly during the first month of postpartum. Our main conclusions are:

•
During the first month of lactation, the mothers did not satisfy the nutritional requirements of the guidelines. The important deviations in some micronutrients suggest that the women would benefit more from individualized supplementation, based on their nutritional status. • Adherence to the HFP was moderate, and increased physical activity and dairy product consumption could be beneficial for maternal health. • BMI may not be a good indicator of obesity in breastfeeding women during early postpartum. Larger cohort studies would help to determine the normal body composition values in this population.

•
The novel multidimensional approach used in this study enables us to evaluate possible deficiencies in specific dietary components and health habits, which could enable personalized interventions in those areas that require attention. • Studies in larger cohorts would be important to provide specific recommendations adapted to the healthy food pattern of different populations.
Supplementary Materials: The following are available online at https://www.mdpi.com/article/10 .3390/nu13061766/s1, Table S1: Natalbén-Lactancia ® nutritional supplement composition; Table S2: AP-Q categories at day 28 postpartum between women with and without preterm delivery; Table S3: standardized loadings (pattern matrix) based upon correlation rotated matrix.  Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.

Data Availability Statement:
The data presented in this study are available on request from the corresponding author. The availability of the data is restricted to investigators based in academic institutions.